v4.2.0

Changes:

• Jinja2 templates for output generation
• Support for HPC cluster (Slurm, GridEngine)
• Support for streamed URL-based data input (OpenDAP, download on demand)
• Sphinx directive to automatically document processes.
• Refactoring of IO handler classes
• Added validators for JSON, DODS links and netCDF formats
• Numerous bug-fixes, additional tests and documentation improvements