message: Update docs for installation
  This fix updates docs for installation through pip (pypi.org).
  The example code has also been updated.
  This will make us ready to release 0.1.0.
diff: TensorFlow I/O is a collection of file systems and file formats that are not
  available in TensorFlow's built-in support.
  -## Developing
  -
  -The TensorFlow I/O package (`tensorflow-io`) could be built from source:
  -```sh
  -$ docker run -it -v ${PWD}:/working_dir -w /working_dir tensorflow/tensorflow:custom-op
  -$ # In docker
  -$ ./configure.sh
  -$ bazel build build_pip_pkg
  -$ bazel-bin/build_pip_pkg artifacts
  -```
  -
  -A package file `artifacts/tensorflow_io-*.whl` will be generated after a build is successful.
  -
  ## Installation
  -Once a package file `artifacts/tensorflow_io-*.whl` is ready, installation could be done through:
  +The `tensorflow-io` package could be installed with pip directly:
  ```
  -$ pip install working_dir/artifacts/tensorflow_io-*.whl
  +$ pip install tensorflow-io
  ```
  -The related module could be imported with python:
  +The related module such as Kafka could be imported with python:
  ```
  $ python
  Python 2.7.6 (default, Nov 13 2018, 12:45:42)
  [GCC 4.8.4] on linux2
  Type "help", "copyright", "credits" or "license" for more information.
  ->>> from tensorflow_io.kafka import KafkaDataset
  +>>> import tensorflow as tf
  +>>> import tensorflow_io.kafka as kafka
  +>>>
  +>>> dataset = kafka.KafkaDataset(["test:0:0:4"], group="test", eof=True)
  +>>> iterator = dataset.make_initializable_iterator()
  +>>> init_op = iterator.initializer
  +>>> get_next = iterator.get_next()
  +>>>
  +>>> with tf.Session() as sess:
  +... print(sess.run(init_op))
  +... for i in range(5):
  +... print(sess.run(get_next))
  >>>
  ```
  Note that python has to run outside of repo directory itself, otherwise python may not
  be able to find the correct path to the module.
  +## Developing
  +
  +The TensorFlow I/O package (`tensorflow-io`) could be built from source:
  +```sh
  +$ docker run -it -v ${PWD}:/working_dir -w /working_dir tensorflow/tensorflow:custom-op
  +$ # In docker
  +$ ./configure.sh
  +$ bazel build build_pip_pkg
  +$ bazel-bin/build_pip_pkg artifacts
  +```
  +
  +A package file `artifacts/tensorflow_io-*.whl` will be generated after a build is successful.
  +
  ## License
  [Apache License 2.0](LICENSE)
  