[drlvm] DRLVM should accept Java6 classes now

[Gregory Shimansky]

Hello

As of revision 572698 DRLVM should not throw UnsupportedClassVersion 
when it sees a class file compiled with Java6 compiler (or with -target 
1.6 by ECJ 3.3). These class files should work with no problems with DRLVM.

For testing I used classlib (trunk) compiled with ECJ 3.3 with -source 
1.6 -target 1.6 and all VM acceptance tests compiled with Sun's javac 
from JDK 6.0.

--
Gregory