[iOS] Language-specific keyboard download regression fix.

[iOS] Resource Download Manager

[iOS] Settings notification bar refactor/prep

[iOS] Direct use of specific language lists for downloads

[iOS] Download error failure handling

[Developer] Add kmlmc command line compiler and environment

[Android] Disable version and copyright text from flashing on splash screen

[Developer] Lexical model compiler CLI

[Developer] Better compilation assertions

Addresses #1964

Fixes iOS Get Started