add data-trunk8-* support

[waitingmyself]

add attribute data-trunk8-* to each element for special settings @rviscomi sorry for my english,i am uncertain if i understand your words

It should not take precedence over the options object in init.

the order of the config is : trunk8.defaults -- trunk8 config -- element attribute and the next will override the last

[waitingmyself]

@rviscomi thanks for your reply,and i have add a new commit to fix the problem.

[waitingmyself]

thanks @rviscomi i learn much more than the code itself ~~