Simple instructions for getting started with Amber

[danports]

• Upload bootstrap script to pastebin (pastebin script simply fetches the latest version of the amber nugget and runs it)
• Get ambernuggets.cc URL up and running
• Create an amber metapackage to enable a simpler install command (Support multiple repository configuration files #44)
• Decide on the right URL to use for the non-pastebin instructions
• Check that pastebin run includes shell and the rest of the environment variables
• The new installation (if you run > amber install amber-client) will not have the required prism libraries (see Import source for all Amber dependencies #29)
• The new installation will try to access an Amber server by default and hang (see Ensure that the package client configuration is persisted when we install a package #33)