Use correct image alignment information and not the identity matrix

[eriksjolund]

Right now the crickconvert command does not store a correct imageAlignment (that relates
to micrometers in the physical world).

$ grep "imageAlignment =" protobuf_schema/st_exp_protobuf/fullsize_image.proto 
  repeated float imageAlignment = 5;
$ 

It just uses an identity matrix.

$ grep identity_matrix{ c++/serialize_to_st_exp_protobuf/serialize_to_st_exp_protobuf.cc
  const std::array<float, 4> identity_matrix{1.0, 0.0, 0.0, 1.0};
$ 

The reason for this is that the crick file format does not contain any information about how the photo pixels relate to the physical real world. This should be fixed.

As long as there is incorrect information in the imageAlignment, it doesn't make sense to introduce
any scalebar (e.g. https://pages.nist.gov/OpenSeadragonScalebar/) in a viewer.