This is a cherry pick of PR #1158 to stable-10.0

[Android] Validate keyboard ID when downloading keyboard from Keyman cloud

[Android] Ensure keyboards list has an entry

Fixes #1120

There are some crash reports coming from `KeyboardPickerActivity.java` because the keyboards list is null (file access error). When the app tries to display the installed keyboards list, this results in the crash.

`getKeyboardsList()` already checks the existence of the `keyboards_list.dat` file, so some of that code is also redundant.

[Android] Fix crashes when input connection or package name is null

This fixes another crash on Crashlytics when the PackageActivity has a null package name.

Cleaning up the console log in #837 introduced a bug when the InputConnection in KMManager is `null` and build variant is `release`.

[Mac] #1090 - Fixed follow-on bug (when Shift is pressed)

Previous fix over-corrected by preventing a non-virtual rule from being used for normal shifted characters. For example, if a rule was supposed to fire for a left curly brace, it would not fire if the rule contained '{' instead of [SHIFT K_LBRKT].

[Mac]#1090 - Fixed problem of selecting wrong rule

I attempted unsuccessfully to find an actual failing case so I could add a unit test for this. Even though I couldn't, I agree that it is the correct logic, so I'm making the change as Marc suggested.

[iOS] Removed unnecessary UIFileSharingEnabled flag

[iOS] #1045,#1046 - Quick fix for OSK layout: disable animation

[Mac] Fixed last stable version number in history.md

[Mac] #1079 - Removed OSK help button for macOS < 10.10 to prevent crash

[Mac] Fixes #1059 - Don't call unavailable selectors on old OS versions