Doesn't retry cuke() except with `-r` argument
Retries cuke() when run under `run-tests`
Fixes doubled slash in couchdb_uri()
Shows last commit after successful run-tests()
Adds bundle exec to rcop()
Detects Rails 4 via bin/rails
Uses numeric colors instead of named for prompt

Changed my default 'blue' color to something more readable against a
black background.  But, I want blue to remain the same regardless of
changing the base 16 colors.
Adds printfc() = printf + color as first arg
Updates warn() to use printfc()
Combines disparate ruby-manager-related warnings
Fixes warning for no default rbfu ruby
Fixes rbfu directory detection
Adds cdenv_vars() to auto-source .env.cd

Automatically exports vars from .env.cd if it exists in a directory, and
removes those variables when moving to a different directory.