Word count differs from other applications

[kuschuermann]

Problem: Word count in CherryTree differs from that reported in other apps, such as LibreOffice Writer.

For example, "What's up, home-boy?" is 5 words in CherryTree, but 3 words in LibreOffice: Neither the apostrophe nor hyphen should be treated as word separators, at least not for purposes of counting words in stories.

Solution: Allow all word separator character(s) to be specified in Settings. If internally implemented as a regular expression, expose this regex directly, as it would allow for significant flexibility at the hands of those who want this. Either way, clearing out that setting should revert CherryTree to its built-in default (the value currently in use).