Tabs init
Add possibility to add and remove tabs
Add possibility to add and remove tabs
Merge branch 'tabs' of http://github.com/martakuzak/MP4_2 into tabs

Conflicts:
	View/mainwindow.cpp
Possibility to add, remove and handle tabs

Conflicts:
	View/mainwindow.cpp
Merge branch 'tabs' of http://github.com/martakuzak/MP4_2 into tabs
Tabs
Merge branch 'tabs' of http://github.com/martakuzak/MP4_2 into tabs
tabs
Merge branch 'tabs' of http://github.com/martakuzak/MP4_2 into tabs
Switching sections - fixed