Fix #19 homesickrc pathname needs a to_s to eval

Also, moved the file evaluation into a new function so the script can be
ran manually which should make testing these scripts easier.
Adding test for clone running homesickrc
Ignore vendor
Add tests for the rc command
Merge pull request #48 from trobrock/fix-homesickrc

Fix #19 homesickrc pathname needs a to_s to eval