Started adding better documentation.
Formatting.
More formatting.
More formatting.
More formatting.
Merge branch 'documentation' of https://github.com/emorydunn/PyTimer into documentation

Conflicts:
	README.md
Cleaning up.
Fixed the order of a comment.
Added a better description.
Added full word matching for units.
If the duration isn't a valid number the problem is caught.
Removed extraneous print statements.
Merge branch 'documentation' into units