misc changes

1) added an exec task (grunt/exec.js) test to check 'app/AppInspector/.sencha/' folder is present as it is needed for Sencha CMD build. - PLEASE RUN 'npm update' AFTER PROJECT UPDATE

2) Re-added 'app/manifest.json' placeholders (name & description).

3) Added German manifest locales.
Merge branch 'master' of github.com:stoe/AppInspector

* 'master' of github.com:stoe/AppInspector: