Add flushAll method

Easier then using patterns.
Fix indenting
Merge pull request #9 from barryvdh/patch-2

Add flushAll method
DRYer flushAll method
Make flush actions actually remove entries from JSON
Add stub of Flatten::kickstart method
Close #8 - Add timestamp to cached pages
Added ability to disable Flatten on certain conditions
Add note on using outside of Laravel
Tweak example
Close #11: Take query strings into account for salts by default
Add some tests for Flatten::kickstart
Update CHANGELOG.md