Adding GEM_PATH to startup script

[dvalfre]

Description of your patch

Add GEM_PATH to Passenger's startup script. Handles #224

Recommended Release Notes

Add GEM_PATH to Passenger's startup script.

Estimated risk

Medium - This affects the startup script of all apps running Passenger.

Components involved

Customers using Passenger as an app server.

Dependencies

N/A

Description of testing done

• Create an app with a source code that includes gem base64 on a version different than 0.1.0.
• Create a v7 environment
• Select Passenger as the app server.
• Deploy the app.
• The app will fail to start, printing a message like You have already activated base64 0.1.0, but your Gemfile requires base64 0.1.1. This can be seen in logfile /data/<app_name>/current/log/passenger.8000.log
• Apply this PR as an overlay on the environment.
• Log into the instance and run su - deploy -c '/engineyard/bin/app_<app_name> restart.
• Confirm that passenger is up & running by checking the log.

QA Instructions

• Create an app with a source code that includes gem base64 on a version different than 0.1.0.
• Create a v7 environment
• Select Passenger as the app server.
• Deploy the app.
• The app will fail to start, printing a message like You have already activated base64 0.1.0, but your Gemfile requires base64 0.1.1. This can be seen in logfile /data/<app_name>/current/log/passenger.8000.log
• Apply this PR as an overlay on the environment.
• Log into the instance and run su - deploy -c '/engineyard/bin/app_<app_name> restart.
• Confirm that passenger is up & running by checking the log.

[scottsherwood]

Patch both sandbox and production env's via cookbook overlay - Fix works perfectly and resolves the issue.

Testing completed:

• Applied the updated cookbook to the sandbox env, shut all instances down, rebooted from a new volume, and everything worked as expcted.
• Applied the cookbook to production, ran a few deploy's, Apply's from the interface along with manually restarting passenger in the console, and again, I can confirm that everything worked as expected.