LDAP: take out ldapUuidAttribute from on-the-fly check, cannot be set by the user and would lead to server error. Fixes oc-1625

set configuvalue in table appconfig back to clob. Likely to break LDAP settings, probably responsible for some bugs with it. Might also cause damage in other apps. That's why it was once already set to clob

Otherwise the file cache and the quota isn't checked

Added failsafes for retrieving remote apps on settings->apps page, in case categories or app data are not found

Added method getAppstoreApps to OC_App
Added minor documentation

LDAP: fix MySQL-query with DUAL table by removing wrong backticks. Got broke when they were added to SQL queries.

Fixes: oc-1369

This didn't work with chunked uploading

This should also fix the dirname problem on windows

fix default values: 1. remove whitespace, don't use emptystring for int, remove empty default for nullable columns to use NULL as default