DataMatter CI

Observations:
  - Most breakage came from changes outside the project (dm-core, extlib changes broke dm-more)
  - Hard to test dm-more in totality, need to install_gems *before* you run rake spec, which is odd
  - (dkubb) "almost all of the problems people are mentioning on the mailing list are Windows related"

Conclusions
  - Run dm-more tests against new code when dm-core is committed to
  - Either automatically install dependency gems prior to running specs, or alter the load path to use edge code

Bonus points
  - Especially post 1.0, being able to run against multiple gem version (so we don't need to release everything when only one gem changes)
  - Publicly available rcov stats
  - Multi ruby
  - Windows testing. I have no idea about this.

Ideas
  - Have a local gem directory for the build (like merb), probably easier than load path shenanigans, can also be used for multi gem versions
  - Chat to merb guys about what they do for CI (answer: they don't, are in the same boat)
  - dbussink has a VM we can use
  - Look at pat's project that runs against multiple gem versions (http://github.com/freelancing-god/ginger/tree/master)