Backport changes from 1.2.0: src/wx.h: Add GPL boilerplate to files which were missing it. src/gdtconvert: Add GPL license boilerplate. src/gdtconvert: Add "Generated" comment to output file.
git-svn-id: file:///home/survex-svn/survex/branches/1.0@3712 4b37db11-9a0c-4f06-9ece-9ab7cdaee568