* error when paddle has a wrong version number.

* Mount local Paddle instead of git clone from remote.
* Use official chinese ubuntu source instead of 163 mirror.

* Check all files by pre commit hooks

* Because in dockerhub, we cannot set the `docker build `running
  directory, we could only use `git clone` command to get the latest
  code if we put `Dockerfile` in subdirectory

* But the `git clone` will checkout the default branch only, so here
  we add a `ENV` in Dockerfile to checkout special branch or tag in
  git repo. We could change it to `V0.9.0` tag when it release.

* Init

* Add numpy deps

* Refine

For multiple installation of paddle, there might be multiple versions of python package at opt/paddle/share/wheels/. We should install the right version.
Ideally, we should remove the wrong versions when install. But it's not easy to do this with cmake.

Change-Id: Ida8a8d60643ad9e42cf1c85776de9122d5ba1392

* also refine install docs, too

* Add noavx to docker
* Not to use directory to split Docker image.

Just forget to add deploy_key to this repository.

to restore successful build status. travis DOCS job on master failed due to permisstion issue: https://travis-ci.org/baidu/Paddle/jobs/159851334  @reyoung, please resolve the permission issue.

* Add documentation build to ci test
* Push master branch doc changes to gh-pages branch

* install wheels when invoke paddle script if current python don't
  have paddle packages, or installed a previous version.
* Also add `make install` to travis

git-svn-id: https://svn.baidu.com/idl/trunk/paddle@1461 1ad973e4-5ce8-4261-8a94-b56d1f490c56

ISSUE=4600925


git-svn-id: https://svn.baidu.com/idl/trunk/paddle@1443 1ad973e4-5ce8-4261-8a94-b56d1f490c56

ISSUE=4600307


git-svn-id: https://svn.baidu.com/idl/trunk/paddle@1439 1ad973e4-5ce8-4261-8a94-b56d1f490c56

ISSUE=4600057



git-svn-id: https://svn.baidu.com/idl/trunk/paddle@1438 1ad973e4-5ce8-4261-8a94-b56d1f490c56

ISSUE=4599563


git-svn-id: https://svn.baidu.com/idl/trunk/paddle@1435 1ad973e4-5ce8-4261-8a94-b56d1f490c56

ISSUE=4599521


git-svn-id: https://svn.baidu.com/idl/trunk/paddle@1434 1ad973e4-5ce8-4261-8a94-b56d1f490c56