Consider adding TestProf

[joshmcarthur]

TestProf comes with a few handy things that I'd definitely appreciate as part of our default testing stack:

• Sampling: It's quite handy on large test suites to do a quicker test run, especially with configuration changes or gem updates rather than running the whole suite.
• Transactional before(:all) - this is handy for the few tests we have that need to set up a 'world' to test with. I find this is more common for things like testing searching, or pagination, where you might need to create several records to test against. The DB time required to setup and teardown those records for each test can add up.
• Verbose logging - output logs to $stdout for a particular example or example group, instead of log/test.log
• Profilers: I guess this is the main purpose of the gem, and a bunch we'd use:
  • Event Instrumentation - measure time spent in DB specifically is quite handy
  • FactoryDoctor - detect instances where records were created when they didn't need to be

Opening an issue initially to see if there's interest in adding this