[Linux] Basic groundwork for kmflcomp to support v10 keyboards

[Developer] Show selected character range in character preview window, not just first character

[Developer] Re-implement Convert-to-character command in web text editor

[Developer] Track deadkeys more reliably in debugger

[Developer] Support CSS, JS and JSON formats in text editor

[Developer] Project window needs to support untitled projects

[Developer] Support printing from ACE text editor

[Developer] Tidy up row selection in web editor

[Developer] Remove old popup menu and attach command event for new menu for text editor

check for icons dir and .ico converted to .bmp
yacc.y LANGUAGE is handled as a string
some linux .gitignore
don't search fof icons dir or .ico in ibus-kmfl

[Developer] Manage focus correctly for setting breakpoints and more

[Developer] Remove Alt+letter/digit and function key bindings from editor

[Developer] Support Escape key in text editor to clear error highlight

[Developer] Support context menu in text editor

[Developer] Remove Alt+letter/digit and function key bindings from editor as they conflict with environment bindings

[Developer] Support context menu in text editor (some commands not yet implemented; this is infrastructure)

[Developer] Restore support for 'reformat xml document' in ACE editor

[Android] Remove ad-hoc distribution of keyboards via keyman:// protocol

* Clean up unnecessary `KMKey_` keys
* Update MainActivity to only download ad-hoc KMP packages.