Project view: add summary table, button to toggle some locales (complete, locamotion)

* Summary table uses a structure similar to the one already available on langchecker, just based on % instead of missing strings.
* Added a button to hide/show complete locales, locamotion locales
* Updated projects data structure: pretty title to display on project page, possibility to hide the new summary table on small projects like https://l10n.mozilla-community.org/webdashboard/?project=snippets_dec14
* Added local config file to .gitignore

At this point #31 should be obsolete.