Bugfix (mostly) Release

Fixed #37. Too many extended commands shown
Fixed bug that caused Hearse to crash on certain network errors
Fixed bug caused by storing empty strings in message history
Fixed #38. Rest on '.' instead of space.
Fixed bold menu entries incorrectly interpreted as group headers
Fixed preferences incorrectly initialized
Support '.' and '-' in multi-select menus
Support \b for backspace in command sequences and fixed formatting when using \n
Changed background to a border and added a border opacity option

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