Linux Libraries Loaded from Installation Location

* libewf and zlib are loaded from their installation locations on Linux
* On Windows and Mac OS X, libewf and zlib are loaded from the datamodel jar file. Java's library path does not cover the expected locations on Mac (like /usr/local/lib and /usr/lib) so we can't load the libraries from their installation locations unless we change the java.library.path JVM arg. That is not favorable because we would have to keep track of three separate java.library.path's and 3 separate configuration files in Netbeans. Libewf and zlib are copied into the datamodel jar file from their default installation location. (/usr/local/lib for libewf and /usr/lib for zlib)
* Reorganized LibraryUtils and SleuthkitJNI's static initialization block to reflect these changes.