Review for 8006225: tools/jdeps/Basic.java fails with AssertionError

[Mandy Chung]

This fixes 8006225: tools/jdeps/Basic.java fails with AssertionError.

Webrev:
    http://cr.openjdk.java.net/~mchung/jdk8/webrevs/8006225/webrev.00/

jdeps maintains a static list of analyzed classes, each of which is 
expected to be from one archive.  test/tools/jdeps/Basic.java calls 
com.sun.tools.jdeps.Main multiple times with different classpath and 
thus the same class came from different path in a different invocation 
of jdeps.  Fix jdeps to keep the data in instance variables.  I 
refactored the analysis from JdepsTask into a new Analyzer class to ease 
further enhancement.

Thanks
Mandy