* cudnn widndows

* "add comment"

* "windows support"

* "fix cmake error"

1. Automatically detect GPU arch by default.
2. Specify -DCUDA_ARCH_NAME=All when releasing PaddlePaddle new version

to create a gradient machine for inference using merged model with parameters
which is genearted by `paddle merge_model`.

* Expose paddle.framework by pybind11

* Export paddle.framework.{Scope, Variable} to paddle.v2.framework.core.
* See python/paddle/v2/framework/tests/test_scope.py for Python usage
* See paddle/pybind/pybind.cc for C++ bind code.

* add copyright

 using the same implemetation as mac os.

* for modern language properties

* DYLD_LIBRARY_PATH is disable after Mac OS X 10.11
* fix clang + gpu compile error on Mac OS
* fix some words and errors in build docs