Isolate field directives scope to make them testable
Add first directive test
Refactor common input field logic into a directive
Simplify edit fields to avoid repetition
Add NumberField Unit test
Test more directives, introduce the attributes field method
namespace edition directives
unit test maChoiceField
Test (and fix) maChoicesField

If someone can make this work with ng-options, I'm all for it because it
saves scopes and all, but I tried for half an hour and failed. MAybe
stackOverflow has the answer but I'm without Internet here so ng-repeat
is my last hope.
Replace number field with more traditional input field
Remove ReferenceField and ReferenceManyField

These are just particular cases of ChoiceField and ChoicesField. By
tweaking the Reference class just a lottle bit, we can avoid a lot of
code duplication and make the code simpler.
Speed up forms by binding the field only once
Merge pull request #166 from marmelab/testable_directives

[RFR] Isolate field directives scope to make them testable