Errors in C export need to report module/register/field context for diagnosis

eg. This is really unhelpful.

Traceback (most recent call last):
  File ".venv/bin/csr-export", line 4, in <module>
    main()
  File ".venv/lib/python3.6/site-packages/csrParse/csrExport.py", line 54, in main
    packageOptions.exporterOptions.exporter.to_source( packageOptions, csrData )
  File ".venv/lib/python3.6/site-packages/csrParse/csr/exporter/c/export.py", line 127, in to_source
    mapExport.generate( thisMap, registerMapName )
  File ".venv/lib/python3.6/site-packages/registerMap/utility/export/c/registerMap.py", line 98, in generate
    self.__createModuleFiles( registerMapName, encapsulatedMemory, moduleElements )
  File ".venv/lib/python3.6/site-packages/registerMap/utility/export/c/registerMap.py", line 118, in __createModuleFiles
    registerMapName = registerMapName )
  File ".venv/lib/python3.6/site-packages/registerMap/utility/export/c/module.py", line 44, in outputModule
    registerMapName = registerMapName )
  File ".venv/lib/python3.6/site-packages/jinja2/asyncsupport.py", line 76, in render
    return original_render(self, *args, **kwargs)
  File ".venv/lib/python3.6/site-packages/jinja2/environment.py", line 1008, in render
    return self.environment.handle_exception(exc_info, True)
  File ".venv/lib/python3.6/site-packages/jinja2/environment.py", line 780, in handle_exception
    reraise(exc_type, exc_value, tb)
  File "venv/lib/python3.6/site-packages/jinja2/_compat.py", line 37, in reraise
    raise value.with_traceback(tb)
  File "registerMap/utility/export/c/templates/idiomatic/module_template.h", line 26, in top-level template code
    {%- for bitField in thisRegister.fields %}
  File ".venv/lib/python3.6/site-packages/jinja2/environment.py", line 430, in getattr
    return getattr(obj, attribute)
  File ".venv/lib/python3.6/site-packages/registerMap/utility/export/base/register.py", line 76, in fields
    registerIntervals = makeContiguous( self._element.bitMap.sourceIntervals, (self._element.sizeBits - 1) )
  File ".venv/lib/python3.6/site-packages/registerMap/structure/interval/contiguous.py", line 33, in makeContiguous
    sortedIntervals = sortIntervals( intervals )
  File ".venv/lib/python3.6/site-packages/registerMap/structure/interval/sort.py", line 39, in sortIntervals
    assert not anyOverlap( intervals )
  File ".venv/lib/python3.6/site-packages/registerMap/structure/interval/overlap.py", line 70, in anyOverlap
    reviewingInterval = intervalSet.pop()
KeyError: 'pop from an empty set'