pass package and version to XSLoader::load

Apparently not passing package and version to XSLoader is sort of a
newer feature, so for greater backwards-compatibility (and less fail
reports), add the two arguments in there.

Change the dzil package plugin so that there can be a version number in
the original file that is replaced when the build is made. This is
necessary for the XSLoader to work during development.
fix incorrect loop bound

The fix for #2 given in 7e66d3905 gave an incorrect bound for this
loop, which would access `gangcount[8]` if it ran.
add missing multiplication

Also related to the work for #2, the multiplication of the final
element of `p` and `gangcount` was missing, and so is added again here.
remove debug statements

Removed all of the debug statements used in tracking down #2.