renaming
fix bug: old gradient selection applied when picking an object
bring dockwidget to front on showTable()
add aboutQt info box
move data/files gui to DataBrowser, refactoring WIP
remove C language from CMake project config
add data browser tool icons
open table + remove file via tool button
open render view again
bold widget title on focus switch
add render view tool icon for "no renderer selected"
replace QTableView subclass by eventFilter
consistently use "*View" names for Table/Render*
superclass for Views
fix visibility toggles
keep render view highlighted until next view is selected; fix set not rendered objects as hidden