[Mac] Minor code cleanup

Merge pull request #1071 from keymanapp/mac-1059-cherry-pick-from-stable-10.0-do-not-call-unsupported-selectors

[Mac] #1059 cherry pick from stable 10.0 (do not call unsupported selectors)

Avoid calls to unsupported selectors on old version of OS 

[Windows] Fix docbook links (alpha)

This fixes the links on the help pages for
* https://help.keyman.com/products/desktop/10.0/docs/common_mac.php
* https://help.keyman.com/products/desktop/10.0/docs/common_linux.php

[iOS] Moved alpha change info to 11.0 alpha section

Having a date and specific version messed up the build (and probably isn't needed)

[ios] Remove reference to Android in history to satisfy App Store review

[iOS] #824 - remove blank buttons from alert screens

[web] (master) If a layer has lower row count to default layer in embedded mode, then Keyman throws an error.

Merge branch 'web-incorrect-row-count-assumption-1055-master' of https://github.com/keymanapp/keyman into web-incorrect-row-count-assumption-1055-master

[web] Fixes #1055. If a layer has lower row count to default layer in embedded mode, then Keyman throws an error.

The low-level event tap already handles detection of mouse events that could make the context out of date.

[Mac] Refactored target-action call from keyView

10.0 stable release

10.0 stable release

P3S6 Beta to Alpha (final run?)

[Mac] #991 - Reverted changes for #872 (to solve more serious bugs)

[Mac] Fixes #894 - Fixed invocation of keyAction (missing self param)