go.tools/oracle: turn emacs integration into minor-mode
go.tools/oracle: turn emacs integration into minor-mode

Define a minor mode called go-oracle-mode. Right now its sole
purpose is to define a keymap but it might later be used to add
hooks or add other features to go-mode.

R=adonovan
CC=golang-dev
https://codereview.appspot.com/13412048

Committer: Alan Donovan <7069e9552f9d110b0a0f326b96f22f63fb99dfc1@google.com>

tmc/mirror-go.tools,t-yuki/go.tools.old,tmc/mirror-go.tools,tmc/mirror-go.tools,t-yuki/go.tools.old,t-yuki/go.tools.old