RPC: Fixed method change lost on source format

- Fixed calling updateUser() when "usersrManager/updateUser" is called.
  Original fix was lost on source format.
Merge pull request #278 from zlamalp/fixup

RPC: Fixed method change lost on source format
GUI: fixed refresh of user name on tab when changed (perun admin - user detail)
Add working with null givenName (firstName) of User to LDAPc

- in main,java when incializing users
- in updateUser when firstName is null
- in createUser when firstName is null
Merge pull request #279 from stavamichal/Ldap-NullInFirstNameOfUser

Add working with null givenName (firstName) of User to LDAPc
Merge pull request #280 from zlamalp/fixup2

GUI: fixed refresh of user name on tab when changed (perun admin - user detail)