Add bower.json to watch list
Merge branch 'master' into topics/watch_bower

* master:
  Release 1.7.1.
  Separate source map updating in sourcefile
  Revert "Do os.platform() check only once."
  Do os.platform() check only once.
  Update pluginHelpers description in docs
  Refactor pluginHelpers block
  pluginHelpers default by regex before filename
  pluginHelpers default to first joinTo file instead of last
  fix #659
Centralize config files array
Run `bower install` on bower.json changes
Fix missed var rename isPluginsFile -> isPackageFile
Reload watcher after bower install
Merge branch 'topics/watch_bower' of https://github.com/brunch/brunch into topics/watch_bower

* 'topics/watch_bower' of https://github.com/brunch/brunch:
  Fix missed var rename isPluginsFile -> isPackageFile
Merge pull request #665 from brunch/topics/watch_bower

Watch bower.json and run bower install