the version of clang on travis ci is 3.3
install libc++-dev and libc++abi-dev if CC is clang
couldn't find 'libc++abi-dev'
travis ci don't have libc++
update submodule 'libj'
update submodule 'libj'
update submodule 'http-parser'
update submodule 'libj'
update submodule 'libj'
pass String directly
reuse JsObject
update submodule 'libj'
reuse StringBuilder
reuse StringBuilder
update submodule 'libj'
update submodule 'libj'