Add figure to the appropriate place

There is a wrong caption in the subsection of 'Launch an instance from an
image' in the 'Controller Node' section of Associate Training Guide. And
there is no figure for it. This patch fix the problem.

Change-Id: I112bbfc9947091e36a55ba0471928b5822c29424
Closes-Bug: #1327017
Merge "Add figure to the appropriate place"