Sort the context right menu in better UX

[hildogjr]

Sort the context right menu and sub-menus:

• Making easy to access (appear first) the most used options;
• Sort the option in better User Experience way.

For example:

1. Text size are sorted as "normal, large, small, tiny, Huge, LARGE, Large, footnote, huge", it will be better in the Latex size order.
2. Add some separator in the context menu to split the most used options.