cctools 855

Refs #35100. This provides a statically-linked `install_name_tool` which could be used to relocate bottles on systems that do not have developer tools installed.

This formula is based on Tigerbrew's cctools, and I'd like to maintain Tiger/Leopard/PPC support in this formula so I only have to maintain one version of the formula.

TODOs:
- [ ] Test to see if cctools 855 works on Snow Leopard (and hence if only two versions of cctools are required, not one per OS)
- [ ] Test if moving files post-build at the end of the formula can be used to avoid patching the makefile on Tiger/Leopard, as it is on newer OSs
I see a lot of identical conditionals, would be good to group them together.