Improved the code that generates the ssh keys for clients and shell users and reorganized it into a central function.

additionally fixes this for client_update

Improved API behaviour: The $params array must contain only the new values and not all values of a record on update. Setting all values does not hurt though, so the change is downwards compatible with older versions.

This reverts commit 4cd62d78.

Dominik authored Feb 25, 2014 and Dominik committed Feb 27, 2014

Erweiterungen für remote-Quota

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Feature can be activated over admin mailserver settings. when activated websites uid is used instead of standard vmail-uid. this only takes effect if web and mailserver are on the same server, otherwise it will be old behaviour. switching this setting when mailboxes exist doesn't matter. Mailboxfolder will be created with website uid for this. access of postfix and dovecot now works over mysql-table mail_user. virtual_uid_maps is changed from static to mysql-table. for dovecot<->postfix communication protocoll is changed vrom lda to lmtp. disablelmtp-column is added to mail_user-table. uid and gid can be overwritten by remoting.
ONE OPEN ISSUE: since remoting has completly changed and mail_user_add function is missing at the moment, this function now was inclulded again. it is important to add the both new lines to the future function and then remove this new one.

- 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