Fixed some typos, whitespace, periods, 80-column lines

Fixed some typos, whitespace, periods, 80-column lines

- typos: LINGUAS manually, rest with help of aspell(1)
- whitespace: some trailing spaces/tabs, one utf-8 NBSP (#xC2 #xA0)
- made most text in docs/ fit in max 80-column wide lines
- consistent trailing periods in sentences in labwc-actions.5.scd and
  labwc-config.5.scd; labwc-theme.5.scd had different consistency,
  changed it follow these other files with sentence-ending periods
- and ", respectively" (comma often used to separate)