Applied the full set of first draft revision edits for the
new migration section for 1.7. Comments from Paul Eggleton.
(From yocto-docs rev: 90586addbc719ecaf7c768b267adf0e988e27b74)
Signed-off-by: Scott Rifenbark <scott.m.rifenbark@intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>