Getting started on .y and .l
Add include.h
More .y
Change include.h
added oprNodeType
Modified include.h
Merge branch 'shining' of https://github.com/wqfish/avl into shining

Conflicts:
	src/include.h
Modified include.h
Modified included.
change include.h
Merge branch 'shining' of https://github.com/wqfish/avl into shining

Conflicts:
	src/include.h
Operator API updated.
yu zheng
added some operators
Merge branch 'shining' of https://github.com/wqfish/avl into shining

Conflicts:
	src/include.h
	src/parser.y
Merge branch 'shining' of https://github.com/wqfish/avl into shining
Operator node function defined.
Add creator.
haha
Merge branch 'shining' of https://github.com/wqfish/avl into shining

Conflicts:
	src/include.h