RPM is a powerful package management tool used by many distributions. The value of having bitcoin-core in Linux distributions that use RPM should be fairly obvious with the coming SegWit soft-fork and the possible block size hard fork, as it would allow users of distributions that include a Bitcoin RPM to keep up to date automatically.
Included in this pull request is a sample RPM spec file that "works for me" on CentOS 7 to build Bitcoin 0.12.0 safely using the recommended version of BerkeleyDB statically linked at build time, and running the necessary tests at build time to make sure the build was successful before the packaging succeeds.