Support java 11 class file

v2.1.0

Support class file from Java 11

Fix jdk 1.6 error

v1.2.2

Fix Class Not Found Error for jdk 6 environment

Support JDK 1.8 and JDK 9

v2.0.0

Rename package and group id

Support field reference search

Use -fref to find the class refer to the specified fields.

Support java 8 class file

Support ASM from jdk 8 to parse files if contains jdk 8