DOCS: update localization notes for developers & translators
DOC: more localization notes
Merge branch 'feature-localization' of github.com:hsogo/psychopy into feature-localization

* 'feature-localization' of github.com:hsogo/psychopy:
  RF: avoid using localized text for code logic
  ENH: update Japanese translation
  ENH: localize dialog titles and messages in wizard.py
  ENH: StaticText must be wider to show non-English characters
  RF: change file path settings in messages.po in ja_JP
  ENH: update Japanese translation
  ENH: support non-ascii calibration notes
  ENH: localize "Input Text" dialog
RF: localization: text length in gui.py depends on lang in use (esp if its multibyte or not)
DOCS: changelog for localization
FF: better gui addText size calculation (fix by hsogo)