Initial attempt at introducing an @mapping class. See 622.
Modifying BNDFUN and UNBNDFUN to use new mapping class. All tests pass.
Merge branch 'development' into feature-mapping

Conflicts:
	@bndfun/bndfun.m
	@chebfun/constructor.m
	@unbndfun/createMap.m
	@unbndfun/cumsum.m
	@unbndfun/diff.m
	@unbndfun/innerProduct.m
	@unbndfun/sum.m
Adding some documentation and tidying up.
Remove MAPPING.SUBSREF() - its too slow.
Reorganise the constructor to improve performance.
Merge branch 'development' into feature-mapping

Conflicts:
	@chebfun/constructor.m
	@unbndfun/createMap.m
	@unbndfun/cumsum.m
Merge pull request #849 from chebfun/feature-mapping

Feature mapping