Remove trailing white-space in a bunch of .tex files.

These are all in src/ and are probably both out-of-date and candidates for removal.

Some maintenance to ensure that the sub-manuals and reference manual build
properly (help/src -> help/src-sml). Dropped the references to src/n_bit
and src/word.

The res_quan manual doesn't seem to build on Macs. Some problem with it
failing to make the theories.tex file. (Still works on an old Linux
machine.)

Initial revision