* Bump for Xcode 10 beta 3
Include a few changes to have green builds, e.g. it seems
`[GKAchievement init]` and `[GKAchievement initWithIdentifier:nil]`
are different now
```
[FAIL] Default constructor not allowed for GameKit.GKAchievement : Objective-C exception thrown. Name: NSInvalidArgumentException Reason: -[GKAchievement identifier]: unrecognized selector sent to instance 0x6000004a48d0
[FAIL] iOSApiCtorInitTest.ApiCtorInitTest.DefaultCtorAllowed : 1 potential errors found in 1426 default ctor validated:
```
* [xtro] Fix EventKit
* [tests] Make intro tests green in macOS Mojave Beta 3
* [tests] Make xtro happy
* Not every old annotations have been migrated (work in progress, to be completed in another PR);
* Sanitation of the data files (e.g. removal of dupes and fixed, by Apple, entries) is done, but not automated (also a work in progress)
Even then this is immediately useful, i.e. better merged before 15.6 gets branched.
Sebastien Pouliot
Alex Soto