merge fixes accumulated during run-up to ESUG plus those collected at ESUG

- tODE support
- fix issue #247: random failures from MetacelloScriptingFetchRecordTestCase debug: #testBasicFetch001
- fix issue #259: When downloading a github repo, should print SHA to Transcript
- fix issue #260: symbolic versions should be registered as a resolved version
- fix issue #261: MetacelloProjectRegistration>>lookupSpec: doesn't always find the right spec
- fix issue #263: `locked` projects should NOT create conflicts, too