Add USER instruction
updated default
add to cli
assume ip_forwarding = 1 by default
Fix #1330 and #1149. Improve CMD, ENTRYPOINT, and attach docs.
rebase docs
add mongodb image example
update help
small fix to docs regarding adding docker groups
Merge pull request #1576 from MatthewMueller/patch-1

updated default -H docs
Merge pull request #1588 from dotcloud/1561_fix_warning_in_tests

assume ip_forwarding = 1 by default
Merge pull request #1513 from dotcloud/add_user_dockerfile

Add USER instruction do Dockerfile
Merge pull request #1607 from TylerBrock/mongodb

Add MongoDB image example
Add mongodb example
Merge pull request #1614 from denibertovic/docs

Small fix to docs regarding adding docker groups
Merge pull request #1596 from metalivedev/1149-easyfixes

Fix #1330 and #1149. Improve CMD, ENTRYPOINT, and attach docs.
Added Tag command to build multiple tagged images in one Dockerfile