Tell us the version when users show us debug logs
Instruct user to set DOCKER_TLS_VERIFY

Signed-off-by: Aanand Prasad <aanand.prasad@gmail.com>
Send debug output to stderr when copying certs
Check all necessary environment variables

If any of DOCKER_HOST, DOCKER_CERT_PATH or DOCKER_TLS_VERIFY are
incorrect, `boot2docker up` will inform the user, and
`boot2docker shellinit` will output the correct commands to set/unset
them.

Signed-off-by: Aanand Prasad <aanand.prasad@gmail.com>
[FIX] Description for --vbox-share. Instead of "during init" it is during "up" command.
Merge pull request #269 from aanand/docker-tls-verify-instruction

Instruct user to set DOCKER_TLS_VERIFY
Merge pull request #246 from SvenDowideit/show-version-in-verbose

Tell us the version when users show us debug logs
Merge pull request #275 from SchumacherFM/fixPR274

[FIX] Description for --vbox-share. Instead of "during init" it is durin...