A change in typescript@next means that dts-critic now gets types for
even more JS code, which means that it can discover problems with those
new types.
This PR disables the errors for now; I'll come back and make changes for
widely-used packages since they are the most likely to benefit from
having correct exports.
* extended loadimagecallback with metadata argument.
* lint.
* extended unit test.
* cleanup test.
* polishing.
* added further type definitions for the blueimp-image-loader.
* merge.
* formatting.
* use interface instead of type definition.
* enhance export definition.
