Changed version number.
Update SPKG.txt and checksums.ini.
Changed checksum.
Trac #16560: Upgrade lrcalc to 1.1.7

Using the upstream based off of here:
http://www.math.rutgers.edu/~asbuch/lrcalc/ but use the one in the
attachments as the root directory is `lrcalc-sage-1.1.7`.

This should (help) fix #14625.

URL: http://trac.sagemath.org/16560
Reported by: tscrim
Ticket author(s): Travis Scrimshaw
Reviewer(s): François Bissey