Merge branch 'develop' into issue/#3062

Merge branch 'develop' into issue/#3062

* develop: (68 commits)
  Added documentation
  update to the translation
  update to the translations
  translation docs now contain basic usage of the Transifex client
  - Replace TinyMCE-enabled filebrowser.tpl by filebrowser_plain.tpl content
  - Remove misc TinyMCE mentions in docs and minifyjs
  - Remove $theme_richtext_editor boot var - Remove "richtext" feature - Remove fix_mce_lf() function - Remove nomce parameter
  - Remove TinyMCE mentions in themes
  - Remove tinyMCE mentions or convert to addeditortext() - Remove $editselect template value
  Remove tinyMCE libraries
  limit the description of the meta tag to 160 characters in /mod/display
  Improved handling of non string values in the config
  Bugfix: Caching of non string cache values now works.
  Reformatted stuff, improved query
  Auto-focus first input field of modal when shown
  Use cache instead of config for storing last proc_run time
  Some added logging
  Bugfix for masses of php warnings
  Rearranged the logging
  Some changed logging
  ...

# Conflicts:
#	view/theme/frost-mobile/js/theme.js
#	view/theme/frost/js/theme.js