[TASK] Improving textarea dimensions

[TASK] Change PageLayoutView hook textarea width

[TASK] Further decreasing page layout textarea width to prevent layout breaks

[TASK] Improving textarea CSS height; 100% height leads to huuuge textarea heights
[TASK] Loading all prism brushes to provide best UX
[TASK] Minimizing "plain" brush: no regular expressions, best performance
[TASK] Updating documentation regarding Prism dependencies and loading order
Merge branch 'master' into t3editor_builder_conf

Conflicts:
	Classes/FlexformT3editor.php
	Classes/Hooks/PageLayoutViewHooks.php