fix nil hash warning in pg info
Fix inaccurate 'internal server error' message

This happened when all 3 conditions were met:
  1) no app was specified
  2) no app could be inferred
  3) app::db shorthand was not used
use lowercase help strings in pg
Fix duplicate gem warning in Gemfile

Group `:development` and `:test` both had `rr` and `rake` pegged at the same
version, and Bundler was complaining.

This commit breaks them out into their own block
Merge pull request #979 from will/two-pg-fixes

Two pg fixes
deprecate account:confirm-billing
Make sample command output match command input
Merge pull request #998 from heroku/doc-patch-scaling

Make sample command output match command input
Merge branch 'gemfile_fix'

* gemfile_fix:
  Fix duplicate gem warning in Gemfile
Never use the PGBACKUPS_URL from the environment

It's not clear from the history why this was introduced in the first
place, but the only conceivable use I can think of is testing against
a staging version of PGBackups, but that can easily be done by
actually adding the staging add-on to an app.
Merge pull request #1001 from deafbybeheading/no-pgbackups-url-from-env

Never use the PGBACKUPS_URL from the environment
An authentication failure from an API key should exit 1.
Merge pull request #716 from keithpitt/heroku-api-key-auth-exit-1

An authentication failure from an API key should exit 1.
upgrade the heroku-api wrapper (heroku.rb)
support PX dynos

This adds support for non-numeric dyno sizes. Currently only P is supported
size is a string
make ps:scale accept lowercase Xs too, as ps:resize does
update usage docs to mention PX dynos
ignore .rbenv-version
bump heroku-api to the released version