Uses not_if to determine if install is needed

execute#creates is run before the not_if block can be executed, and will
and will skip running the command if the file exists.  Since that can't
be helped, I have removed the file and replaced it with the same
functionality in the not_if block.

This also adds a version check to the installed version to make sure if
the versions don't match, we go forth with the install.
Adds a force option
Moves variables to top of file and fixes

Makes use of the tmp variables that we were using in the rest of the
commands to dry up the code a bit.

Also fixes the shell outs to wkthmltopdf --version.