Scatter the useful files into subdirectories by theme.
This is maybe a little random, but better ideas seem thin on the ground.
* `build/' is for build tools: scripts and build-tool fragments which
are handy for building projects.
* `doc/' is for documentation, and things which help with producing
documentation, such as styles.
* `licence/' contains licence documents.
* `m4/' will be for Autoconf machinery, but it's not there yet:
splitting up `aclocal.glob' will be a job for another commit.
* `src/' contains source code which is shared among many projects.
This commit just moves the files about. Some of the scripts have had
their `.in' suffix stripped because they should no longer be hacked by
Autoconf or anything similar, but none of the content is modified.
~mdw / runlisp / commit