Improved Richtext-TV options-handling, added modxRTEbridge

[Deesen]

• @Dmi3yy modxRTEbridge is ready now. I thought adding to assets/lib/ makes sense.
• Richtext-TVs recognize now "editor"-param. Themes can be switched via "theme"-param. This way multiple editors on the same page are possible. Tested with
  • 2x Codemirror (TV-option: {"editor":"Codemirror"} ) + [*content*] switched to Codemirror
  • TinyMCE4 {"editor":"TinyMCE4"}
  • TinyMCE4 {"editor":"TinyMCE4","theme":"creative"}
  • TinyMCE4 {"editor":"TinyMCE4","theme":"mini"}
  • CKEditor4 {"editor":"CKEditor4"}
  • CKEditor4 {"editor":"CKEditor4","theme":"mini"}
  • mixing Tiny v3 and v4 on the same page was not possible due to JS-conflicts ;-)

• added modxRTEbridge to assets/lib, supporting also inline-mode / frontpage-editing with Tiny4 now -> Switched to modxRTEbridge extras-evolution/tinymce4-for-modx-evo#1 (comment)