Reviewed-by: Trust Me

In CppTools, keep cpp file settings in plugin and settings page
via shared pointer and apply to mime DB in
extensionsInitialized() (after CppEditor has loaded
and registered the mime types).

Task-number: 252299

Fixes: Introduce a cpp settingspage containing file naming conventions (lower case and suffixes). Reorder VCS settings pages.

Task: 241959, 248085

RevBy: Optics/Naming checked by con
Details: Give IOptionPage an id() to differentiate from trName(). Make showOptionsDialog return a bool (applied) and give it an optional parent. Change Cpp and form class wizards, give them a Configure... button to change those settings.