This makes get_maintainers.pl behave a little better.

Reported-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Anthony Liguori <anthony@codemonkey.ws>

My IBM email address will be unaccessible after August 23rd, 2013.

Signed-off-by: Anthony Liguori <anthony@codemonkey.ws>

Add a .mailmap file so 'git shortlog' can map the unfriendly
pre-git-conversion author entries to real names.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>