Fix for new regexp library ($ isn't end of line any more).
Don't assume . is in PATH.
R=golang-dev, dsymonds
CC=golang-dev
https://golang.org/cl/5175052
No longer do we generate HTML from it; instead the input
file is already in HTML but has template invocations to
extract programs from other files.
Delete htmlgen, which is no longer needed.
Add tmpltohtml, which runs the templating code.
R=golang-dev, dsymonds, adg
CC=golang-dev
https://golang.org/cl/4699041