Update Readme.md
updating read me for cache hit and index usage
correcting readme
updating the appropriate calculation of cache hit
fixing bug in cache hit rate query (typo)
Merge pull request #1 from quarterdome/master

There was a typo in a cache hit rate query.
Fix division by zero
Bring in heroku pgbackups:transfer
update help strings
refactor exec_sql
Adds support for postgres nine point two

fixes #2
Update init.rb

updating to correct formula
update url
fixing calculation on cache hit formulas
fix of table for cache hit
Adds blocking to readme
Merge pull request #8 from gregburek/readme-blocking

Adds pg:blocking example to readme
improve help messages
correct help about what pg:blocking does
improve error message when procpid not passed in