Adding CeSymm documentation and improving README
Adding a couple more CeSymm options

Suggested in #1
removing version short option
Adding CeSymmMain from symmetry project.

Removed from https://github.com/rcsb/symmetry in
revision 30fea423d608e7c9832d99c4afccdfd21fb5172b

Adds a few minor additions, including help and version parameters.
Improve CeSymm distribution package

- Use shade plugin to build a single jar file
- Modify assembly configuration to specify the correct jar version in the bash script
- Shade excludes classes from jmol which conflict with our versions