Improved usability

Added:
* plugin will tell you if the word was not found and give you a list of similar words to try
    * requires "pyenchant" to be installed in the external python, can be installed via `pip install -U pyenchant`
    * if "pyenchant" is not installed, it will default to a super dumb quick suffix stripped alternative
* plugin will tell you if you don't have a word selected
* keybinding file for linux
* settings file shortcuts in the preferences menu