rotation. Also clean up the handling of units, by putting the
conversion factors in only one place, and clean up the
expression-parsing but removing all the copies of the same error
message.
[git-p4: depot-paths = "//depot/solvespace/": change = 2093]
instead of tying that to whether the shaded model is shown. And
rewrite all URLs to solvespace.com, not www.solvespace.com, and get
rid of the nag screen that I just added because opening the website
with ShellExecute seems to freeze a bit on startup.
[git-p4: depot-paths = "//depot/solvespace/": change = 2044]