Merge pull request #341 from nsendetzky/master

Removes phpexcel extension as requirement
Merge pull request #342 from nsendetzky/master

Improves import and export of CSV files in ExtJS controller
Merge pull request #343 from nsendetzky/master

Adds label to imported texts and mbstring module requirement
Checks for invalid rows in text import
Removes test with PayPal as the results are not stable enough if PayPal isn't available