Bash: update `hman` command to use better tmpdir, & handle errors better
ipython notebook: enable MathJax
Vim: remove my custom "Make" command, since dispatch.vim defines one
Bash: move `hman` from bash function to script; improve it

It now uses a better location to save its files ($TMPDIR instead of /var/tmp) and pre-processes its input, so that things like tables are converted to nice, pretty images, instead of the ugly raw-code images they were before (see `hman troff`).
bash: use better `trash` command, from Morgan Aldridge.
bash: move 'mark' script to proper location in ~/bin