Update copyright notices for 2014, add missing notices

I noticed that the copyright notice on hackage was out of date.  While fixing this, one thing lead to another, and I ended up going on a copyright rampage:  I followed the advice given in the [GPL howto](https://www.gnu.org/licenses/gpl-howto.html) and updated copyright years in all released files.  I also added copyright notices to two files.  I double checked time-spans using the git history whenever I was in doubt.

From the HowTo:

>The copyright notice should include the year in which you finished preparing the release (so if you finished it in 1998 but didn't post it until 1999, use 1998). You should add the proper year for each release; for example, “Copyright 1998, 1999 Terry Jones” if some versions were finished in 1998 and some were finished in 1999. If several people helped write the code, use all their names.

> For software with several releases over multiple years, it's okay to use a range (“2008-2010”) instead of listing individual years (“2008, 2009, 2010”) if and only if every year in the range, inclusive, really is a “copyrightable” year that would be listed individually; and you make an explicit statement in your documentation about this usage.