Possible fix for being able to save over files when using import plugins.
Set the correct window as modified when using an input plugin on OS X.
Update translation base.
bug fix: use Hunspell WORDCHARS to help in tokenization of words
the remainder of the spell check bug fix
try to prevent issue where first save as uses the Sigil's scratchpad directory for Linux and Sigil's program directory on Windows.
update changelog.
Add user guide and plugin info epubs.