Split up switch-case into separate methods

- part of EditEntity API refactoring
- get rid of huge switch-case and split it into methods
- remove the EXCLUDE parameter from the EditEntity API
- move aliases operations into seperate ChangeOpAliases class
- move sitelink operations into separate ChangeOpSiteLink class

Bug: 48137

Change-Id: Ic27774f67f8728acbb48cbf945fda063791096cf
Merge "Split up switch-case into separate methods"