Binary build release process

[Michael Hope]

As part of closing out the Windows toolchain card, I've documented the
binary build release process at:
 https://wiki.linaro.org/WorkingGroups/ToolChain/BinaryBuild/ReleaseProcess

The interesting thing is a script that pulls builds from S3 and posts
them to Launchpad.  There's a curl command at the end that does the
upload and might be useful.

-- Michael