Squashed 'bogo/' changes from fa4581f..9b85329

9b85329 Fix a bug in which handle_backspace misses "y"
f408037 [API-BREAKAGE] handle_backspace() now only returns a new raw_sequence
d2201ad [API-BREAKAGE] More flexible handle_backspace()
f7141c0 Remove the note about being functional

git-subtree-dir: bogo
git-subtree-split: 9b85329a408ded4cead3539cecba12984d5d7650
Merge the latest API change in bogo-python

Merge commit 'df1c3906ed0ce8e396e8cc00f4eb4543713765a7'
Adapt to the new change in bogo.core.handle_backspace()
Merge pull request #30 from lewtds/handle_backspace_api_change

Adapt to the new change in bogo.core.handle_backspace()