Removed workarounds

- Display server name in all web domains select fields so that you know which domain from which server you select.

- Added: First version of client api access with client user credentials
- Changed: 
  - merged remoting_lib and tform into one new base file where appropriate
  - moved some methods into helper methods
  only those methods remain in remoting_lib or tform that are completely
  different in these files or are only used in one of them
- Changed: added check of _GET array in json api handler

http://www.howtoforge.com/forums/showthread.php?t=62691

Added: Changed idn function to support multi-line fields (like mail forward)

- need to have the pecl idn and intl modules installed
  or
- have the idna_convert class in the classes/idn/ path

Fixed/Implemented: replaced intval() by $app->functions->intval() in all interface functions due to big number problem in intval()

Added: Form fields are disabled if a client is not allowed to edit a domains main settings

- Implemented: FS#1935 - Add minimum allowed seconds Value for DNS zone records

Fixed: FS#2109 - Email address validation via API method(s) is inadequate (and results in false-negatives)