Allow using non US Standard S3 regions

Added `options.endpoint` which is passed on to `knox` to allow
explicitly specifying the S3 endpoint.

Updated readme and sample.
Merge pull request #23 from urbancups/master

Allow using non US Standard S3 regions
released 0.0.9 - added explicit setting of endpoint by @eladb
added contributor
Fixed an issue with OptiPNG 0.7 or higher

Check the return code from OptiPNG instead of STDERR since OptiPNG outputs all activity logs into STDERR by default.
Display activity logs from OptiPNG 0.7 or higher

Monitor updates on STDERR and redirect to logger.
Merge pull request #24 from nozaq/patch-optipng0.7

PNG optimizations fail with OptiPNG v0.7 or higher
Merge pull request #29 from JoshuaGross/master

Fix CSS parsing: non-image attributes and whitespace
added update
do throw errors, I want anything that fails to be uploaded to cause a deploy error