Sub-orbital CKAN

• Locates Steam on OSX
• ckan update implented; fetch the CKAN online!
• ckan available lists available mods.
• ckan install now installs from the network.
• ckan show dies with less mess when a mod is not installed.
• The --ksp=... switch can be added to any option, specifying where KSP is installed.
• ckan config gamedir /path/to/gamedir sets the default gamedir location.
• --debug and --verbose can be added to any command, to see more of what's happening inside.
• KSP version is auto-detected.
• ckan by itself displays help.