test-cert generation scripts: Add text info to root cert .pem files.

BUG=none
R=rsleevi@chromium.org

Review URL: https://codereview.chromium.org/134163012

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@248665 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 248665