add "env" to Code
allow modifying "env"
config support for php environment
Correct GEM_PATH and GEM_HOME setup

GEM_PATH and GEM_HOME were being joined through a simple concatenation. If root does not end in a / this fails (which is the case when using iron_worker run). Using File.join ensures the / is added if needed.

Also any system gems were not being included if ENV['GEM_PATH'] was empty. Some environments will always have GEM_PATH set to the proper paths. But often it is empty an we are just relying on the RubyGems defaults (i.e. ENV['GEM_PATH'] is empty but Gem.path is not). Updated the code to use Gem.path instead of ENV['GEM_PATH'] so system gems are used as a fallback (useful if running locally but doing a remote build and therefore there is not a __gems__ directory or if doing a local build but some gems have native extensions and are skipped).
Update configuration article link
Merge pull request #147 from rcs/patch-1

Update configuration article link
Merge pull request #148 from eric1234/patch-1

Correct GEM_PATH and GEM_HOME setup
add log streaming support
Merge pull request #149 from thousandsofthem/add-log-streaming

add log streaming support
Updating gems.
Reverting fix which breaks remote build in rare cases.
Merge pull request #145 from thousandsofthem/add-config-for-php

config support for php environment
Merge pull request #138 from thousandsofthem/add-env-to-code

Add env to Code
add runner for node runtime
remove useless condition
utf-8 everywhere!
freeze rubyzip version to 0.9.9
Merge pull request #151 from thousandsofthem/node-runner

Add runner for node runtime
add config option for node
Merge pull request #155 from thousandsofthem/add-config-for-node

add config option for node