translation view uses entry.lang to temporarily change the locale

This change also introduces a new way to "guess" the user-provided
locale:

* en_US.UTF-8 (and any other valid locale name) passes without
  any further lookup
* de or deutsch (and any other valid locale *alias*) is used as
  key for python's locale_alias dict.

  If not found, issue a warning and supply some similar names, e.g.
  if you set "entry.lang = deu" you will get a list of similar aliases
  like eu, de and de_lu.
remove *.lic.txt and rename hyphenation files
add The LaTeX Project Public License 1.3c
add patterns for ca, es, hr, it, pl, pt and ru
adjust hyphenation pattern building