RFR: JDK-8034199 Add 'reconfigure' target for re-creating a configuration

Wed Feb 12 13:36:35 UTC 2014

Sometimes we need to re-run configure, due to changes in configure 
files. Make detects such changes and forces a new run of configure.

If configure was run with a long command line, it's tricky to get this 
right again. However, this can be done automatically by the Makefile.

By adding a new target 'reconfigure', if we have an existing 
configuration, configure will be ran again with the same arguments as 
last time.

Bug: https://bugs.openjdk.java.net/browse/JDK-8034199
WebRev: 
http://cr.openjdk.java.net/~ihse/JDK-8034199-add-reconfigure-target/webrev.01

/Magnus