Fix a few minor issues with building/running inside msysGit

[tianon]

$ project/make.sh binary test-integration-cli
# WARNING! I don't seem to be running in the Docker container.
# The result of this command might be an incorrect build, and will not be
#   officially supported.
#
# Try this instead: make all
#

---> Making bundle: binary (in bundles/1.4.1-dev/binary)
Created binary: /c/Jenkins/gopath/src/github.com/docker/docker/bundles/1.4.1-dev/binary/docker-1.4.1-dev.exe

---> Making bundle: test-integration-cli (in bundles/1.4.1-dev/test-integration-cli)
/c/Jenkins/gopath/src/github.com/docker/docker/project/make/test-integration-cli: cannot make pipe for process substitution: Function not implemented
/c/Jenkins/gopath/src/github.com/docker/docker/project/make/test-integration-cli: cannot make pipe for process substitution: Function not implemented
/c/Jenkins/gopath/src/github.com/docker/docker/project/make/test-integration-cli: line 11: >(tee -a $DEST/test.log): ambiguous redirect

[tianon]

https://jenkins.dockerproject.com/job/Windows/label=windows/49/console

[tianon]

(temporarily hacked up the Jenkins windows builder to build my branch to demonstrate the glory)

[jessfraz]

Sooooo legit

On Friday, January 9, 2015, Tianon Gravi notifications@github.com wrote:

(temporarily hacked up the Jenkins windows builder to build my branch to
demonstrate the glory)

—
Reply to this email directly or view it on GitHub
#10014 (comment).

[jessfraz]

LGTM

[LK4D4]

I have no idea what's going on here, but logic is changed. Now data from LookPath will override DOCKER_BINARY. Maybe that's your plan...

[tianon]

This was actually killing me. We were shelling out to which in order to ask the OS where docker is, when that's literally what exec.LookPath does (but also what exec.Command itself will do, which is how we could even shell out to just which in the first place).

I figured the point of touching dockerBinary at all was to get a full path to the binary, so I switched the logic a bit to run LookPath regardless such that DOCKER_BINARY could be set to something like docker-1.4.1-dev and have that be searched on the PATH as well here instead of in every single exec.Command.

[LK4D4]

Thanks, got it.

[crosbymichael]

LGTM

[tianon]

YESSS https://jenkins.dockerproject.com/job/Windows/label=windows/50/console