Provide feedback once language is selected

[hpbl]

Right now, when the user selects a programming language, the "Supported Languages" section just disappears. Depending on the size of your screen, you might not even notice that a new component was added to the bottom where the user is supposed to select the sections he wants for his README.

I think of two possible ways we could give feedback:

1. Automatically scrolling to the composer
2. Adding some text indicating what the user is supposed to do.

Feel free to choose the one you think it's best (but if you choose 2, make sure it does not look bad)

Thanks!

[pallymore]

I can take this one.