[TASK] Rename ContentController to CoreContentController

Allows provider extensions to contain core content, fluidcontent FCEs, page templates and backend module templates without collisions.
[TASK] Added a very basic HTML and link parseFunc setup
[BUGFIX] Prevent call on possibly NULL Form instance
[TASK] Add Travis build script
[TASK] Add basic bullet list element
[TASK] Add divider element
[TASK] Add basic image and textpic templates
[TASK] Fix some labels and ordered list start index
[TASK] Move Grids of Image carrier elements to Template from Partial
[TASK] Further improvements to Image/Textpic elements
[TASK] Complete the HTML content element
[TASK] Remove forms - intent is to use other extensions for forms
[TASK] Restructure new content wizard items
[TASK] New content wizard lists all plugins under "plugins"
[TASK] Early return and hide tab if no plugins registered
[TASK] Drop Textpic element type
[TASK] Clean up trigger and getTemplateFilename in Provider
[TASK] Truncate Default (fallback) template - no Preview, empty Main
[TASK] Sort language labels
[TASK] Fix use of default template and triggering on custom CTypes