fix(expressions): properly detect invalid expressions ending with ,
fix(expressions): provide detailed error msg for invalid pipe expressions
refactor: use Pratt'd parser for expressions in text nodes

Closes #286
test: add a test for a repeater and a global pipe

Fixes #281

Closes #284
adds custom attributes

Close #257
adds a handler for class attributes
adds a handler for model and value attributes

Close #257
fix #224 onChange timing issue - Firefox vs Chrome and IE

Close #228
updating api doc

updating hashspace template notation and added some missing paragraphs

Close #259
Make samples keyboard accessible

Close#169
White space management