fixed unused call warnings by using '_ =' or changing method signature to throw instead of return a bool

[developer] Update BCP 47 selector in Keyman Developer to support lookup and more stringent checks

[developer] Fixes crash after save or source view change in OSK Editor

[Web] AltGr emulation fixes

Fix loop in test for match and nomatch validity

Fix OSK missing keys on older Android configurations

[developer] Workaround for use-after-free in Delphi string management causing EInvalidPointer exceptions

Fixes #786

Fixed call for finishing activity when cancelling keyboard download dialog

[developer] context and index are not valid in the output of a match or nomatch rule

Rewrite all context help links to match Developer 10.0 help paths and identifiers

This fixes #304

Reference: https://jira.appcelerator.org/browse/TIMOB-16358

Older versions of WebView have an issue with transparent/gradient backgrounds. The symptom was the OSK slowly loading keys individually, and having the OSK be missing keys.

A workaround fix is styling the body `background-color` alpha to 1.0.

## Testing configuration
* Android API level 22
* Nexus One emulator
* French-French keyboard

Proper escaping for popup keys between Swift and JS

Rewrite all context help links to match Developer 10.0 help paths and identifiers; update language help to track keywords more reliably

Default output null guarding

Fixes display of longpress special keys.

Add version history for 10.0 beta releases for Desktop and Developer

[Android] Disable text suggestions and hide system OSK when resuming app

This handles all transitions where an external app/dialog using the system OSK returns to the Keyman app such as resuming:
* from WebBrowserActivity
* from Android Oreo's "Add to dictionary" dialog