Skip inactive environments while getting the project.

In case one wants to, there is new `--include-inactive` option.
Make build links relative.

In case absolute links are prefered, there is `--abslinks` or `-a` option.
Fixes #29.
Command to remove old builds.

Fixes #65.
Add rebuild-aliases command to force aliases rebuild.
Merge branch 'master' of github.com:nvahalik/platform-cli
Updated README.md with platform list output, fixes #37
Added environment:ssh command, fixes #36
Add environment:relationships command, fixes #32
Add logout command and change local build to not require logged-in credentials
Fixes #23 and fixes #49
Small fixes
Merge pull request #61 from kotnik/get-inactive-envs

Skip inactive environments while getting the project.
Merge pull request #67 from kotnik/pr/relative-links

Make build links relative.
Merge pull request #68 from kotnik/pr/clean-builds

Command to remove old builds.
Merge branch 'master' of github.com:nvahalik/platform-cli into nvahalik-master
Changed to a project-category fix-aliases command
Merge branch 'nvahalik-master' for pull request #69
Added additional checks/messages/weird-behavior-handling
Merge pull request #71 from platformsh/36-add-platform-ssh-passthru

36 add platform ssh passthru and relationships display
fix line endings *SIGH*