Add missing chewing_aux_String_static.

Signed-off-by: Yao-Po Wang <blue119@gmail.com>
Read len in chewing_set_selKey

Closed #115
test: avoid feature test warning for GCC
Replace 'INCLUDE' with 'AM_CPPFLAGS' in Makefile.am
and do some required modifications

Remove the old 'AC_SUBST'
Change 'AM_CPPFLAGS' to 'DEDAULT_CPPFLAGS'
Merge pull request #116 from hiunnhue/master

Replace 'INCLUDE' with 'AM_CPPFLAGS'

Closed #68, #114
Print $DEFAULT_CPPFLAGS at configure
Add new API chewing_new2

Closed #31
Add test cases for chewing_new2
Update document for chewing_new2