support niix extension
updated edatatables extension alias
Merge branch 'master' into niix

Conflicts:
	ExportAction.php
small improvements
Merge branch 'master' into niix
remove Yii::import calls with hardcoded alias, now everything should be imported manually before using the extension
Merge branch 'master' into niix

Conflicts:
	ExporterView.php
Merge branch 'master' into niix
Merge branch 'master' into niix
use new loadQuery method signature
fix fetching pk
Merge branch 'master' into niix
Merge branch 'master' into niix
fix excel export
Excel cannot process empty cells with format set to Date
fix header height - Excel didnt show header row
set charset
replace <br/> to spaces in headers in xls export