Matlab developer documentation page update

This PR reviews the `Using Bio-Formats in Matlab` documentation page:

- restructure the page into 3 sections based on the M files: `Opening image files` describes the usage of `bfopen`, `Reading from image files` describes the usage of `bfGetReader` and `Saving files` describes the usage of `bfsave`
- reviews the description of the `bfopen` complex cell array output
- verify and fix the code snippets
- simplify the `Saving files` section to use examples based upon `bfsave`
- add additional internal link as well as a link to the Javadocs for the OME metadata section
- highlight code blocks using Matlab pigments

Given this proposed restructuration, does it make sense to call `data = bfopen('/path/to/data/file');` at the beginning of each code snippet in the first section?