[HACKERS] GSoC 2017 weekly progress reports (week 3)

During this week, I continued my work on testing and created my first patch for gist index. I have also started working on the hash index. In summary, I have done following things in this week.

1) updated tests to check false positives

2) created tests for index scan

3) fixed a small issue with "make check"

4) fixed a small bug in the code by updating the location of predicatelockpagesplit().

5) read the source code of hash index to understand its implementation