use run_on_modifications instead of run_on_changes to avoid multiple runs after saving files with VIM.  See: https://github.com/guard/guard/issues/495
Merge pull request #16 from redterror/run_on_modifications

use run_on_modifications instead of run_on_changes to avoid multiple runs...
bumps travis test version to 2.1.1
bumps version to 1.0.4