Add option to create the Latex template in the target directory

[stefanlippuner]

Changes:

• Add parameter --doc-copy-template that creates a template at the specified location.
• Add cheby.data as package data to setup.py, s.t. it's copied during installation.
  • Template generation works after installation using setup.py install

[tgingold-cern]

Thanks! And thank you for keeping documentation up to date.

[stefanlippuner]

You're welcome! Thanks for the very fast merges :)