docs: update cfchecker with wps execute

docs/source/processes/cf_output.txt

@@ -0,0 +1,35 @@
+CHECKING NetCDF FILE: vwnd.sfc.2015.nc
+=====================
+WARNING: The conventions attribute specifies COARDS, assuming CF-1.0
+Using CF Checker Version 2.0.6
+Checking against CF Version CF-1.0
+Using Standard Name Table Version 28 (2015-01-07T10:24:11Z)
+
+ERROR (2.6.1): This netCDF file does not appear to contain CF Convention data.
+
+------------------
+Checking variable: lat
+------------------
+
+------------------
+Checking variable: head
+------------------
+INFO (3.1): No units attribute set.  Please consider adding a units attribute for completeness.
+
+------------------
+Checking variable: vwnd
+------------------
+WARNING (2.5.1): missing_value and _FillValue set to differing values
+
+------------------
+Checking variable: lon
+------------------
+
+------------------
+Checking variable: time
+------------------
+WARNING (4.4.1): Use of the calendar and/or month_lengths attributes is recommended for time coordinate variables
+
+ERRORS detected: 1
+WARNINGS given: 2
+INFORMATION messages: 1

docs/source/processes/index.rst

@@ -37,6 +37,25 @@ The WPS Parameters are:
      Is the output parameter to provide the report of the CF check as text document. 
      It is a WPS ComplexData type with MIME-type ``text/plain``.
 
+WPS process execution
+---------------------
+
+An example execution of the cfchecker process with public available data:
+
+http://localhost:8092/wps?service=WPS&version=1.0.0&request=Execute&identifier=cfchecker&DataInputs=resource=http://www.esrl.noaa.gov/psd/thredds/fileServer/Datasets/ncep/vwnd.sfc.2015.nc&RawDataOutput=output
+
+The process is called with key/value parameters, synchronously and with direct output (``RawDataOutput``).
+
+The resulting text document of the cfchecker report looks like the following:
+
+.. literalinclude:: cf_output.txt
+    :linenos:
+
+CDO
+===
+
+to be continued ...
+