Version 0.31.3

* Use absolute paths and allow env var overrides for gettext scripts
  -- bug #152020 (Rodney Dawes)
* Allow shell-backticks (and other shell features) in variable names
  -- bug #152448 (Danilo Segan)
* Fix typographical error in intltool.m4
  -- bug #153630 (Rodney Dawes)