recent dev work

 * [tests] adds previously skipped tests
 * [minor] adds TODO
 * [fix] assert whether git is installed [#24]
 * [minor] add grunt-mocha dependency
 * [minor] clean up start path logic
 * [wip] refactor tests
 * introduce mocha for testing
 * install grunt on travis bootstrap
 * use ./node_modules/hoodie-server/bin/start if hoodie-app module not found
 * check for hoodie-app existence before starting.
 * no <3's for single letter vars
 * minor refactoring and commenting