done seashell.UI re-write

Performance test cases
1) Done updating performance tests. Much improved performance. create
seashell wrap spend < 2us, while save a value to seashell.data cost 36
us. The performance doesn't degrade a bit when number of data in
seashell.data reach 100,000.

seashell.data
1) Now support "." in data matching event

seashell.Validator
1) Regard "." in query string as a isa operator
2) add isa operator to determine if a string-type is or is derived from
a given string type

seashell
1) Change places where "." is appropriate
2) seashell.type() now return "element" for element

seashell.types
1) Types now support borrowFrom property, a much simplified way to
borrow methods among types.

seashell.Widget
0) Complete widget framework based on widget.md
2) Update all widgets & writers for new widget framework.
    a) Remove input widgets, since now any property can be binded,
input widgets no longer necessary.
    b) Rename 'value' renderers for every widget

seashell.transit & seashell.animate
1) Re-consider transition define structure, to allow more simple
implementation of seashell.transit.
2) Merge animate & transit into one function: seashell.animate
3) Better support for chained animation. And animate support .css() in
chained function
4) WidgetList support chained animation, syntax similar to d3.