RFR: 8055772 : (xxs) get_source.sh : version check assumes English localization

[Mike Duigou]

Hello all;

This is a very small fix suggested by bitter_fox which forces English localization for the 'hg version' message which is parsed by get_source.

webrev: http://cr.openjdk.java.net/~mduigou/JDK-8055772/0/webrev/
jbsbug: https://bugs.openjdk.java.net/browse/JDK-8055772

Reminder: 8055331 also still needs review:

jbsbug: https://bugs.openjdk.java.net/browse/JDK-8055331
webrev: http://cr.openjdk.java.net/~mduigou/JDK-8055331/0/webrev/

Mike