EG-4168 Updating contributors.md list for OS 4.7 release branch (corda#6782)

Author: ivanterziev-r3

CONTRIBUTORS.md

@@ -17,6 +17,7 @@ see changes to this list.
 * amiracam
 * Amol Pednekar
 * Andras Slemmer (R3)
+* André Lopes
 * Andrius Dagys (R3)
 * Andrzej Cichocki (R3)
 * Andrzej Grzesik (R3)
@@ -178,7 +179,9 @@ see changes to this list.
 * Robin Green (CIBC)
 * Rodrigo Bueno (Itau)
 * Rodrigo Gonçalves (Itau Unibanco)
+* Rodrigo Vieira
 * Roger Willis (R3)
+* Roman Plášil
 * Ross Burnett (Macquarie)
 * Ross Nicoll (R3)
 * Rui Hu (Nordea)
@@ -220,4 +223,5 @@ see changes to this list.
 * Vitalij Reicherdt (Commerzbank AG)
 * Wawrzek Niewodniczanski (R3)
 * Wei Wu Zhang (Commonwealth Bank of Australia)
+* Xavier Leprêtre
 * Zabrina Smith (Northern Trust)