Tweak types to reflect ejson
Add get/3

Returns a default value if a lookup fails.
Allow lookups in empty lists without crashing
Merge pull request #2 from christophermaier/tweaks

Update types to reflect ejson support
Add get/3 to support default values
Fix bug in empty json handling
Fix default test to return a valid type
Fix spec for get, it can also return 'undefined'
Add dialyzer target to Makefile
Export json_term and json_object types
Update spec for ej:get; it support json_plist()
Add ej:valid/2 for validation EJSON terms via declarative spec

Introduce the ability to validate EJSON objects using a declarative
spec shaped like EJSON, but with rules for validating instead of
literal values. The unit tests in test/ej_valid_test.erl show some
example usage.

This code working, but the API and format of the specs is subject to
change a bit.
Merge branch 'ej_valid'
Add "any_of" and "any_value"
Fail when top-level JSON is not an object
Automatically determine types for any_value and any_of
so that error messages work for missing fields.
any_of should fail when spec is empty
Merge pull request #3 from jkeiser/master

Add any_value, any_of, top-level JSON type validation
Fix type specs

- Add any_of and any_type to ej_spec_type()
- Allow found_type and expected_type to be 'any_value'
- Organized type defs alpha ordering
Refactor helper function type_from_any_of
make dialyzer now depends on all to ensure code is compiled
Add some comments to internal functions