mkmf.template fixes

Fix for the PGI compiler to treat a backslash as a normal character, and not as an escape character in quoted strings.
Removed out of date options for the Intel compiler.
Added options_mod.f90 to path_names that were missing it (test_quad_*_interp).
Corrected typo in input.nml for obs_total_error that was causing fail in preprocess.

New obs converter for Solar Induced Fluorescence

This converter is for the 'harmonized' SIF data in netCDF format.
The full documentation for the converter can be found in the observations/obs_converters/SIF directory.

POP documentation typo fix

This fixes a couple minor typos in the DART documentation for POP. The meaning is unchanged.

Improved support for generating synthetic observations

Improved MATLAB scripts and new scripts for cam-fv make it simpler to generate synthetic observations evenly spaced around the sphere.

The Fortran program create_sphere_obs now accepts namelist options for observation levels and time. The errors used for radiosonde observations in create_sphere_obs are now taken from the NCEP (or ECMWF ) error module.

Bug fix: The Fortran program create_sphere_obs now correctly uses Pascals for pressure values.

Support for identity observations added to obs_info

The obs_info program can be used to summarize obs sequence files containing identity observations as well as real observations.
There is an option to output the summary information from obs_info (observation types, times, and counts)as a .csv file.

AMSUA bugfix

The convert_amsu_L1.f90 converter was not retaining all the observations from all the input files.
The output now accurately reflects the input.

Manhattan v9.10.2

Added templates for pull requests, bug reports, and feature requests.
Updated documentation download instructions and added instructions for developers.

change default GitHub branch

Replaced the default branch ("Manhattan") with "main". "main" is now the latest and stable version. The HEAD of "main" will be the source of releases using the vX.Y.Z format.

Greatly improved documentation, new 'preprocess' methodology

'preprocess' now uses an XXXXX_quantity_mod.f90 that will allow future specification of units and other attributes. The documentation is now served via reStructuredText documents instead of html - this allows us to serve the documentation
through many different formats and services. https://dart.ucar.edu has been updated.

CAM6 80-member reanalysis

This is the final configuration used to produce DS345.0
That dataset is being served on the NCAR Research Data Archive:
https://rda.ucar.edu/datasets/ds345.0/#!description