Nth PR on develop branch for easybuild-docs, for N=5

still bits and pieces to improve, but ok to receive the first round of feedback
add nesting, and a non-easyconfig file, just for kicks:

```
$ find set_of_easyconfigs/ -type f             
set_of_easyconfigs//GCC-4.8.3.eb
set_of_easyconfigs//foo.txt
set_of_easyconfigs//tools/bzip2-1.0.6.eb
```