ClassAnalyzer works with JDK 7 b75

[Mandy Chung]

Alan, Mark,

JDK 7 b75 is promoted.  I update the class analyzer to with
the latest b75 com.sun.tools.classfile library that was changed 
for the fix for 6888367 [1].

If you have a copy of the ClassAnalyzer.jar built from the
jigsaw/tools repo without this changeset, you need to run
with JDK 7 b74.  Or pull this changeset and run it with 
the latest JDK 7 promoted build.

I added a tag "jdk7-b74-classfile-lib" to the jigsaw/tools 
repo in case anyone needs the class analyzer to work with 
JDK 7 b74 for any reason.

In addition, the class analyzer now has the capability to merge
modules.

Thanks
Mandy

[1] http://hg.openjdk.java.net/jdk7/tl/langtools/rev/6ba399eff2cb