Thai Language Support for Google Service

Adds Thai language to the Google service's language list by cherry
picking 3606e6902b2e6a0768042f65c8b63c3ba2177e32 from mistaecko's fork.
Additional Languages for Google TTS

Adds in the mappings for Bosnian, Esperanto, and Tamil so that they can
be used via the Google TTS service.
Minor Formatting for Google TTS Thai Mapping

Adjusts the Thai language row to be formatted like the others in the
Google TTS mappings.
Update to Version String

Uses "Google Changes" now instead of "Google Caching" to reflect the new
language support.
Language Information in README

Adds a blurb to the project's README.md in the root about the added
languages provided by the fork.
Update README

Adds information about the changes to the Configuration screen with
regards to the keyboard binding.
Update Version Tag

Adds "+ Unbind" and shortens the "Google Caching" tag to just "Caching".
Allow Esc/Delete/Backspace for Unbinds

Modifies the Conf_keyPressEvent handler such that if the user presses
either the Escape, Delete, or Backspace keys, the keyval will be stored
as None.
Update to README

Expands README to mention that Backspace and Delete will also allow the
user to unbind a keyboard shortcut.
Display Unbound Shortcuts as "Unassigned"

This adjusts the KeyToString function to return "Unassigned" when keyval
has no value (rather than "Unknown", which can still be reserved for
when there is a value, but the system cannot tell what it is).
Don't Repeat Yourself for Conf_keyPressEvent

Adjusts the Conf_keyPressEvent logic such that it gets its field label
from the return of KeyToString instead of having its own version of the
label.
Merge feature/{google-languages,unbind-shortcuts}

Brings in the new language codes and the ability to unbind keyboard
shortcuts from the Configuration screen.

Conflicts:
	README.md
	awesometts/main.py