Improve the getting started guide
Improve the getting started guide

Here is list of improvement:
- Add 2 intermediate full samples of code that can be compiled and ran
- Link to Runc.md page for runc installation
- Fix typo at the "Task Wait and Start" section
- Fix missing commands to run sample code at the getting stated guide
- Explicitly State go 1.8.x or above and link back to golang install page

Signed-off-by: Roy Inganta Ginting <c5a3051c5868146e7d9ad65ffb52f7f4bb843ab3@gmail.com>

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