Fix bug #5 in command parsing.

Closes #5
Forget to uncomment stuff.
Another typo

Should really find a way to run those unit test on windows.
Added some tests.
Use regex to unfold arguments.
Addressed comment so we use space instead of comma in enumeration argument.
Fixed unit tests
Added unit tests for folded argument classes.
Added unit tests for folded argument classes.
Addressed @mgermain's comments
Refactored functions and classes related to argument templates
Merge pull request #61 from MarcCote/command_parsing

Command parsing