patched agnoster prompt theme.
update agnoster. one icon is missing.
Merge branch 'master' of github.com:mcecot/prezto

# By Markus Cecot (1) and markus cecot (1)
* 'master' of github.com:mcecot/prezto:
  patched agnoster prompt
  patched agnoster prompt theme.

Conflicts:
	.gitmodules