RGB Matrix: if a head includes a dimmer channel, it will be controlled by a RGB Matrix

UI: Fixed QLC+ website URL click event
Reviewed all the fixtures with heads to include a dimmer channel
Updated docs
error in qlcchannel_test
some more fixes in tests
Merge pull request #204 from tornel/error-in-test

Fixed qlcchannel and aboutbox test units
Added fixtures: Clay Paky A.LEDA Wash K5, Clay Paky A.LEDA Wash K10, Clay Paky A.LEDA Wash K20
Added heads to Clay Paky fixtures
Allow VC sliders to control RGB matrices
Revert commit 68ba4fd7 - it breaks local file access...
Function attributes cleanup; fix EFX attributes (index was not passed to Function::adjustAttribute)
Updated dutch translation
Update languages in command line documentation.
Fixed typo in Dutch translations
Merge pull request #206 from joepadmiraal/master

Updated Dutch translations.
Fixture Editor: removed untranslatable strings
Added fixture: American DJ Sweeper Beam Quad LED
Added fixtures: American DJ Ultra Bar 6/9/12
Added fixture: American DJ Inno Color Beam Quad 7
Added fixture: American DJ Inno Color Beam LED (thanks to Louis Gutenschwafe)
NEW: RGB Matrices can now be converted to Sequences and imported into Shows
RGB Matrix: fixed sequence steps durations