Add build scripts for twig extension
Make S3 download url customizable through ENV
Merge branch 'twig' into twigs3
Make S3 download url customizable through ENV
Merge branch 's3_url_env' into twigs3

Conflicts:
	bin/compile
Update Imagemagick version
defend against invalid composer.phars
Merge branch 'master' into twigs3
PHP/5.6.0RC4
PHP/5.5.16
clarify that Bob is a Python app, refs #78, #71 and #50
Merge branch 'master' into twigs3