hg: build-infra/jdk8: Added boot_cycle.sh, a script that builds openjdk twice, the second time using the first as the boot jdk.

[fredrik.ohrstrom at oracle.com]

Changeset: 61eb8ec239f7
Author:    ohrstrom
Date:      2012-09-11 00:02 +0200
URL:       http://hg.openjdk.java.net/build-infra/jdk8/rev/61eb8ec239f7

Added boot_cycle.sh, a script that builds openjdk twice, the second time using the first as the boot jdk.

+ common/bin/boot_cycle.sh