refactor(parser): pass FilterMap to expression eval instead of parser constructor
test(ng_mustache): added a test for filters
fix(parser): disallow filters in a chain and inside expressions
fix(selector): Allow two directives with the same selector

Fixes #471
Closes #481
style(forms): change currentErrors to errors
chore(pubspec): move unittest into dev_dep
chore(demo): Add simple controller to TodoApp
chore(test): add missing test for ng-change

Closes# 399
fix(eval access): Do not crash on null cached value

Fixes #424
chore(build): More debugging in Travis output
fix(select): Corrected NPE if select multiple nested in ng-if

Closes #428
style(ngModel): change currentErrors to errors
fix(NgComponent): Handle errors while loading CSS

Closes #411
fix(ng-class): array syntax should not insert nulls

Closes #513