commands: Added 'Description' fields to Command, Argument, Option
core/commands2: Added descriptions for 'add', 'block'
core/commands2: Removed test subcommands
core/commands2: Added descriptions for all the existing commands
cmd/ipfs2: Added descriptions for 'init', 'tour'
core/commands2: Better formatted descriptions for 'mount'
commands/cli: Added a helptext generator
commands/cli: Helptext spacing fix for root command output
commands/cli: Output command path in Parse
cmd/ipfs2: Output generated help text on error or help flag
core/commands2: Updated root help text