fix(tests): Allow TLS

Fixes https://github.com/deis/deis/issues/2230
docs(managing_deis): add MDS removal instructions
docs(*): specify required CoreOS version
Merge pull request #2352 from johanneswuerbach/patch-6

fix(tests): Allow TLS
fix(build.sh): fail on errors in Dockerfile two-tier builds

Without "set -e" at the top of each build.sh script, errors would
not propagate to the parent "docker build" process. In the case
of controller, this was masking a missing dependency which is now
fixed.
fix(registry): prefix "apt-get install" with "apt-get update"
Merge pull request #2368 from carmstrong/docs-add_remove_mds

docs(managing_deis): add MDS removal instructions
Merge pull request #2369 from carmstrong/add_coreos_version

docs(*): specify required CoreOS version
Merge pull request #2362 from mboersma/catch-build-sh-errors

fix(build.sh): fail on errors in Dockerfile two-tier builds
fix(logspout): bump packet size to 1048576

By default, linux's socket receivebuffer is set to 256. The kernel
doubles this value to allow space for bookkeeping overhead when it is
set, therefore our maximum packet size is only 512 bytes. Bumping to a
much larger number will prevent an issue like this happening again.
Using SetWriteBuffer sets the operating system's transmit buffer
associated with this connection, and SetReadBuffer sets the operating
system's receive buffer.
ref(logspout): use UDP conn