bc @1.06 version update 1.06.95 and readline variant

[eli@…]

I was adding a readline variant to the bc port and ran into a bug with 1.06. bc 1.06 won't compile against readline newer than version 4. This has been fixed in the unreleased bc branch, there just hasn't been a release tagged as stable in twelve years.

This patch:

• updates bc to 1.06.95, the last non-stable release in 2006. Note that most distros have been on this release for some time (Debian since 4 or 5; RHEL as of 6)
• adds a readline variant