2.1.20161227191302: Bugfix resolving references to document fragments. (#74)

* Bugfix resolving references to document fragments.

2.1.20161216210732

Tweak cmap to better propagate filename down. (#69)

1.21.20161215163938

Restore open ended lockfile dep.

1.21.20161206204028

Adjust package dependencies to be more specific about versions.

1.21.20161206181442

Fix fetcher_constructor to default to None instead of DefaultFetcher.

1.21.20161202201331

Bump version to 1.21

2.0.20161122040508

Bump major version number, because of backwards-incompatible changes.…

1.20.20161122192122

Add cache test.  check_exists checks cache.

1.18.20161005190847

Bugfix for validating "class" field. (#61)

1.18.20160930145650: Optimize validate (#60)

Validation can now either fail fast (raise_ex=False) or fail with
explanation (raise_ex=True).  Improve validation performance by using fail fast
when checking unions.  Optimize record validation by performing explicit check
for "class" first.  Improve validation error reporting for unions when one of
the types is an exact match for class by suppressing errors for other types in
the union.

Other changes:
* Use unicode strings more consistently.
* makedoc applies table styling
* Add version constraint to lockfile package dependency