Update .mailmap

- List names alphabetically by Firstname Surname
- Replace tabs with spaces
- Add missing name

Change-Id: Ib320dad316e0f6e3e95363c4d6a64744032db857
Signed-off-by: David Pursehouse <david.pursehouse@sonymobile.com>

.mailmap

@@ -1,5 +1,6 @@
-Shawn Pearce <spearce@spearce.org>	Shawn O. Pearce <sop@google.com>
-Shawn Pearce <spearce@spearce.org>	Shawn Pearce <sop@google.com>
-Shawn Pearce <spearce@spearce.org>	Shawn O. Pearce <spearce@spearce.org>
-Saša Živkov <sasa.zivkov@sap.com>	Sasa Zivkov <sasa.zivkov@sap.com>
-Saša Živkov <sasa.zivkov@sap.com>	Saša Živkov <zivkov@gmail.com>
+Roberto Tyley <roberto.tyley@guardian.co.uk> roberto <roberto.tyley@guardian.co.uk>
+Saša Živkov <sasa.zivkov@sap.com>            Sasa Zivkov <sasa.zivkov@sap.com>
+Saša Živkov <sasa.zivkov@sap.com>            Saša Živkov <zivkov@gmail.com>
+Shawn Pearce <spearce@spearce.org>           Shawn O. Pearce <sop@google.com>
+Shawn Pearce <spearce@spearce.org>           Shawn Pearce <sop@google.com>
+Shawn Pearce <spearce@spearce.org>           Shawn O. Pearce <spearce@spearce.org>