Improved mechanism which updates translation key on startup

- Added new dependencies to "traverse" and "esprima". Esprima is a
library which allows to parse javascript code and extract the syntax.
Traverse helps to traverse the resulting syntax tree.
- Introduced new mechanism to parse mustache templates for i18n
statements
- Introduced new mechanism to parse javascript files for i18n statements
- Improved middleware which loads the translations and delivers it as a
require-js file
- Removed unecessary menu items in navbar