TINY-6728: Redirect content apis to rtc plugin (#6434)
TINY-6728: Redirect content apis to rtc plugin (#6434)

* TINY-6728: added namespaces to rtc runtime api

* TINY-6728: moved undo level creation to rtc runtime api

* TINY-6728: separated rtc into raw and rtc

* TINY-6728: redirected content apis to rtc plugin

* TINY-6728: removed unused parameter and improved minification by variable reuse
tinymce/tinymce,tinymce/tinymce,TeamupCom/tinymce,tinymce/tinymce,TeamupCom/tinymce