IOS-2735 comments out the calling code for disableAllSyncChannels(). It has known Engine issues causing crashes on grouped devices.

IOS-2743 diables the OS's auto locking while pEp Sync Wizard is shown. Background: Desktop pEps seem to take longer to show Sync Wizard and it sucks when the iOS device is then locked already while waitng.

IOS-2735 saves per-account-pepSync-enabled state in core data, uses that everywhere and enables only identities with CdAccount.pEpSyncEnabled on startup.

IOS-2736 adds static lib target for usage on macOS, changes code that need to be changed to be macOS 10.10 compatible.

IOS-2736 adds objc PEPLogger plus some build settings change to be able to mix Obj-C and swift in one project

IOS-2659 rm test that obviously has never been executed (did not inherit from XCTestCase). Also adds dummy test to base class for getting nicer visual output in Xcode when running tests.