Notifications: constrains for notif objects added

- no two TemplateMessages with the same templateId and locale can exist
- no two Regexes with the same regular expression can exist
- no two Receivers with the same target and locale can exist
- created new PerunExceptions for each case in Notification module
GUI: handle aborted request (can't contact server)

- When request to server is aborted by browser (can't contact server), then
 status code of response is 0. Request must be handled in onResponseRecieved().

- Fixed display of connection lost widget in main GUI. Display it only
  when request is aborted by browser.
Merge pull request #565 from zlamalp/gui

GUI: handle aborted request (can't contact server)
UTILS: print also timestamp in pwdm log

- Also add help text for ldaps settings.
Change rules for getting rights for groupManager on attributes

 - change rules on member-resource attributes: only rights on any assigned
   group to resource are needed, add comment with definition of this rule
 - change rules on resource-group attributes: add comment with
   definition of this rule
 - change rules on user-facility attributes: groupManager need rights on
   any group (under resources of facility) which is from the same vo
   like some of users member, add comment with definition of this rule
 - change rules on user attributes: only has groupManager in vo where
   user has any member, add comment with definition of
   this rule
 - change rules on member attributes: only has groupManager in vo, where
   the member has membership, add comment with definition of this
   rule
 - change rules on vo attributes: change rights from NEVER to only
   has groupManager in vo, add comment with definition of this
 - do NOT change rules on group, resource, facility and host attributes
Merge pull request #566 from zlamalp/ldap

UTILS: print also timestamp in pwdm log
Merge pull request #562 from stavamichal/attributesRightsForGroupAdmin

Change rules for getting rights for groupManager on attributes
Fix and add some minor changes to XML extSource

 - xml extSource can send html header if it is set in configuration
 - fix closing of SSL connection
Merge pull request #567 from stavamichal/fixAndAddSomeMinorsToXMLExtSource

Fix and add some minor changes to XML extSource
remove limitation for testing machines from the master branch
SERVICES: Fixed ldap service for dc base

- When dc object is base of perun entries, we must add it
  at least one structural class (domain).

- When getting current ldap state, load also dc object using
  filter on objectclass=dcObject.
Merge pull request #569 from zlamalp/ldapservice

SERVICES: Fixed ldap service for dc base
GUI: unselect services in table after force propagation is started
Merge pull request #570 from zlamalp/gui

GUI: unselect services in table after force propagation is started
Notifications: skipping null values in messages

- new TemplateExceptionHandler created for skipping undefined values
  retrieving from java code
Merge pull request #568 from mvocu/engineNew-cleanup

remove limitation for testing machines from the master branch
Merge pull request #563 from jirmauritz/notification

Notifications: constrains for notif objects added and skipping null values of TemplateMessage
added 2 new modules
-rootMailAliases
-rootMailAliasesMail
added 2 new modules for root mail aliasses
member expiration in synchronizator

-checking if member is disabled or expired, if yes, validating/expiring him depending on expiration date (if member is after expiration date, he is expired)