Added validate pull request script
Updated documentation about gzip filters
Merge pull request #1968 from adis-me/improvements/1967-update-documentation

Updated documentation about gzip filters
Correct heroku Profile details to match new stages start script location

Per https://devcenter.heroku.com/articles/play-support the Procfile should contain:

```
web: target/universal/stage/bin/{your project name}
```
Fix typo in ScalaWS.md

s/ore/are/
Merge pull request #1972 from davidillsley/patch-1

Correct heroku Profile details to match new stages start script location