Rake compiler dev box fixes

I believe this should get the rake-compiler-dev-box setup working and creating gems for 1.9.3, 2.0 and 2.1.

I added some rake tasks to automate the setup of the rake-compiler-dev-box and another to copy over the latest tiny_tds source onto the box before triggering a compile.

Additionally, I added in a patch to FreeTDS that we've been running in production for over a year that fixes logins with more than 30 characters in them.