fix classpath for pam-extension
use correct code conventions (sun/oracle) instead of eclipse code conventions
clean code

- remove useless javadocs, like "get x" for getX, "set x" for setX or "(non-Javadoc) @see x" for overriden methods
- better exception handling to not use Exception
- small improvment in generics (better for inheritance)
use commons-codec to create password hashes fixes #2

tested on debian 7.1 with java
java version "1.6.0_27"
OpenJDK Runtime Environment (IcedTea6 1.12.6) (6b27-1.12.6-1~deb7u1)
OpenJDK Server VM (build 20.0-b12, mixed mode)