Added describe, comments, subtasks.  Messy
add doc string for subtasks
added comment command
comments display git-log style
show subtask open/closed status
use existing table formatter for subtasks
describe uses table formatter but has slightly annoying bug rendering multiline descriptions
better formatting for describe
add some transition constants
add reverse flag to comments subcommand
moved --reverse flag to in front of issue id
on second thoughts keep the flag at the end of the line for now to match with the stop command
added some readme stuff for the new commands
fix Simpsons quote
add example for reversed comments
rejig readme and correct errors
fix another readme error
more explanation for the installer
rejig readme
further copy tweaks