While working on MR !230 I noticed that the options read I entered into several plugins could not be read after reading the image.
**The patch fixes problems reading options in plugins and adds option checking in the readtest.cpp.**
In particular, the reading test does the following additional actions:
- reads options before reading the image;
- compare the options read with the options returned by the reader after reading the image;
- compares the format and size of the returned image with the format and size returned by the reader.
