Added flexibilty when saving integer types to netCDF3
Refactor common code and fix for PEP8 1.4.6.
Merge pull request #5 from rhattersley/netcdf_int_fix

Refactor common code and fix for PEP8 1.4.6.
Merge pull request #745 from esc24/netcdf_int_fix

Added flexibilty when saving integer types to netCDF3
Enhanced guess_bounds docstring.