The idea is great and I admire your lovingkindness.
There are some aspects I would mention, though, that you should take under consideration. (I graduated in Cultural Anthropology and did work with asylum seekers from Chechnya). I assume you're serious about what you want to do, not just go-there-once and forget about it, so I also write dead seriously.
First of all - language and cultural differences. Don't underestimate these. It's a very false assumption that people all around the world share the same values, ideas and understanding. It could happen that you want to do something good, and they would treat it as patronising for instance and get offended. Mind the gender issues as well. And above all they are not at their best, on the contrary, they are scared, alienated, impoverished, tense... Not an easy crowd to get along with. You should have some professional to assist you, someone knowledgeble you could talk to.
Secondly - I have been teaching Hebrew to a small group of people for free. The average age is +30, all persons university graduades, and they DO want to learn. But because there is no fee, they simply don't come to classes, don't do the homework! I could not have made it easier for them - I made all the materials, put them online and send them by e-mail, recorded readings in mp3, printed the handouts and brought paper and pens to the classes so that everyone is equipped. It doesn't work. They don't come regularily, they don't work at home. My mother, a psychologist, laughed at me and said that I have to charge for the classes and even take a collateral from them that will be returned only under the condition that they have 90% attendance and do homework. I don't know about asylum seekers, but I wouldn't be surprised they completely ignore you (not in bad spirited manner). This also happens with the language, the Chechens I worked with simply did not learn at classes. The result was a TOTAL FAILURE. Again, it's not their fault, I don't mean that. The system was broken. It's not enough to just come and teach.
Thirdly - I assume you will be dealing with adults. Adult education is very much different than teaching children. It's not the good place to elaborate on that, but the basic principle is that you have to rely on these people's previous experiences, concepts, ideas. They are adults, so they are not "blank pages" to be filled in with knowledge, they will not easily accept everything you say. They have their own ideas, thinking patterns, views, so you have to often ask questions such as: "What does it remind you?", "Does it look familiar?", "Have you ever encountered...", "How do you understand...". Asking these questions seems like slowing down the teaching process, but this is adult education - you will not go around these issues, as people will start telling you their experiences and thoughts anyway, and if they do it on their own, it will mean "I am not dumb, I also have my say, we're equal" rather than: "He's a really good teacher, I should share my views and see what he thinks". It's tricky.
And finally - I am not sure if vocational training is what they really need. I might be wrong, but based on my experiences in Denmark and to lesser extent in Berlin, all the programs that we had for immigrants failed miserably (again, please, I don't mean anything bad, I blame the system, no the poor people who were forced to migrate). It most often shows that the best we can do is to get them housing, some money, and really focus on providing excellent, inclusive education for their children. I know it's harsh, but that's what I have seen with my very own eyes.
My personal opinion, based on tens of interviews I had with the Chechens, Palestinians, Turks, Iraqis, Somalis and Sudanese is that they are deprived of the social aspects of life, not the economic ones. They look around and they can see you go to Starbucks, but they can't. They can't go to a store, to the movies, to read a book, drink tea and enjoy themselves. They cannot take a phone and call a friend to chat and gossip, organise a party or put on nice cloths and make-up. That's what's really painful when you are surrounded and immersed in out consumptionis culture. They want to have a share in that as well. You could say, well, first you have to work, then you can play and have fun. But it is VERY possible thay they will never get to the point when they can earn for similar consumption of goods and culture. And then they are doomed to misery, poverty, and all bad stuff you hear on CNN.
I don't want to discourage you from teaching programming. It's a great idea. But I just want to draw your attention to that maybe it would be nice to take them to a park, drink coffee, cook together, learn their names and pronounce them properly (very important), learn a few phrases in their languages, encourage your friends to also build social relations with them,
tl,dr: be interested in them as human beings.
(p.s.: in general the demographics of the migrants is an interesting topic in its own right, I think that those who seek asylum in Europe these days are often from the "middle class" in their countries of origin, often more progressive, more open-minded, better educated than the general "Western-White" public thinks. It's the long cultivated view of the alien "barbarian hordes". Some of them will do very well - if they had a grocery in Bagdad, they will manage in Stockholm. If they were accountants back in Egipt, they will open offices in Birmingham. These will not need to learn to code and start from scratch).