[install-guide/f21-branch] it's redhat.com, not redhat.org

[pbokoc]

commit 35c693511d1d2e4a3587e9bd17419be7d09fcb53
Author: Petr Bokoc <pbokoc at redhat.com>
Date:   Mon Dec 8 23:34:44 2014 +0100

    it's redhat.com, not redhat.org

 en-US/Next_Steps.xml       |   26 --------------------------
 en-US/Revision_History.xml |    2 +-
 2 files changed, 1 insertions(+), 27 deletions(-)
---
diff --git a/en-US/Revision_History.xml b/en-US/Revision_History.xml
index 9f7c4e7..4afbb86 100644
--- a/en-US/Revision_History.xml
+++ b/en-US/Revision_History.xml
@@ -14,7 +14,7 @@
 				<author>
 					<firstname>Petr</firstname>
 					<surname>Bokoč</surname>
-					<email>pbokoc at redhat.org</email>
+					<email>pbokoc at redhat.com</email>
 				</author>
 				<revdescription>
 					<simplelist>