tphyahoo has been working on sx help files, command naming, and some
argument passing.

1. sx help files

For easier folowing, I've separated this into a single branch:

https://github.com/veox/sx/commits/docfix

3 commits, not sure about

https://github.com/veox/sx/commit/27c980b665d5be3d288860cbecb2eb929d767755

Should be safe to merge. I'll go ahead if no one objects.


2,3. command naming and passing arguments

This certainly warrants a little discussion.

https://github.com/spesmilo/sx/issues/21
sx set-input should take a transaction on stdin and emit a transaction
on stdout

https://github.com/spesmilo/sx/issues/19
Have consistent naming for BLOCKCHAIN UPDATES sx commands

This would change the command syntax and break some folks' workflow.