README: Fix Docker Installation URL
Load RVM GPG signature
README: Latest MRI is 2.1.5
README: Ubuntu is LTS and bumped to 14.04.1
nginx: Fix startup command; comfig not working
nginx: New entry pint made some config redundant
nginx: run as user nginx
nginx: fix error.log path
nginx: fix pidfile path
nginx: reenable access log
nginx: fix configuration location
nginx: full path to cert in config
README: specify tested nginx image version
README: add links to PSQL and RonR
Update docker ps output in README