OpenGL 4.4 and ARB extensions added as well as NV_gpu_shader5 functions
Merge branch 'master' of git://git.code.sf.net/p/estrelaeditor/code into estrela-new
Added workaround to avoid crash on OSX after `Close All Pages` (closes #190).

The issue is with wxwidgets (filed as ticket 15417); the only workaround I
have been able to find is to disable this functionality on OSX (as there
are other alternatives to closing tabs in groups). The issue only happens
when the last tab is closed from the drop down menu linked to editor tabs.