Update docs/README.md

[leezu]

Update docs/README.md file following https://github.com/apache/incubator-mxnet/commit/c789d020449393f177d903515ff4f80a3f616bc6. That commit only updated docs/python_docs/README.md and missed the docs/README.md

Both files contained duplicate content. Resolve by linking in docs/README.md to docs/python_docs/README.md when Python docs are discussed.

Thanks @aaronmarkham for pointing out the problem

[mxnet-bot]

Hey @leezu , Thanks for submitting the PR All tests are already queued to run once. If tests fail, you can trigger one or more tests again with the following commands:

• To trigger all jobs: @mxnet-bot run ci [all]
• To trigger specific jobs: @mxnet-bot run ci [job1, job2]

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CI supported jobs: [website, unix-gpu, windows-cpu, centos-gpu, sanity, edge, clang, windows-gpu, unix-cpu, centos-cpu, miscellaneous]

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Note: Only following 3 categories can trigger CI :PR Author, MXNet Committer, Jenkins Admin. All CI tests must pass before the PR can be merged.

[leezu]

@mxnet-bot run ci [unix-cpu]

[mxnet-bot]

Jenkins CI successfully triggered : [unix-cpu]

[leezu]

@mxnet-bot run ci [unix-cpu]

[mxnet-bot]

Jenkins CI successfully triggered : [unix-cpu]