define decode_class_name function + refactoring
decode easyblock to obtain module name instead of doing a half-ass job
add unit tests for encoding/decoding class names
always remove unwanted chars from module name (e.g., to obtain vsc_tools for VSC-tools
replace '-' with '_' in module names, fix docstring for remove_unwanted_chars
replace '-' with '_' in module names, fix docstring for remove_unwanted_chars
fix typo

Merge branch 'decode_class_name' of github.com:boegel/easybuild-framework into decode_class_name

Conflicts:
	easybuild/framework/easyblock.py
Merge pull request #618 from boegel/decode_class_name

properly decode easyblock to module name