Removed deprecated file builder_client.go
* Builder: simplify the upload of the build context. Simply stream a tarball instead of multipart upload with 4 intermediary buffers. Simpler, less memory usage, less disk usage, and faster.
* Builder: reorganized unit tests for better code reuse, and to test non-empty contexts
* Builder: added a regression test for #895
Merge branch 'master' into simpler-build-upload
use go 1.1 cookiejar and revome ResetClient
* Builder: upload progress bar

Fix progress bar
add basic support for unix sockets
add the possibility to use multiple -H
add tests
update docs
Merge branch 'master' into add_unix_socket-feature
gofmt and test sub directories in makefile
add testall rule
batch apt-get install operations for speed

The dockerbuilder Dockerfile was installing one package per apt-get
install operation.

This changes it so that consecutive run apt-get install operations are
batched into a single operation.
*Builder: warn pre-1.3 clients that they need to upgrade. This breaks semver, but our API should still be in 0.X versioning, in which case semver allows breaking changes.
* Builder: remove duplicate unit test
* Remote API: updated docs for 1.3
Merge branch 'master' into simpler-build-upload
update docs