Add --pull option to feature/hotfix switch

Fixes #105
Remove parenthesis.

Ruby doesn't require parenthesis if there are no arguments needed for a
function; so I removed them!
Add documentation for f/h switch --pull
Docs: --clean and --pull are independent
Adjust documentation and allow hotfix --clean

Feature and hotfix switch man pages now show [options] instead of [--clean]
[--pull]. These man pages are also properly spaced now. Aditionally, allow
hotfix --clean AND/or --pull. Before only one option could be used at a time
because maxArugments was 4.
Merge add-pull-option-to-switch (#107) into master

Add --pull option to feature/hotfix switch

Fixes #105

Conflicts:
	bin/feature
	man/feature-switch.1
	man/feature-switch.1.ronn