Provide Functionality to Unpack wiff files if required

Sometimes, it would be useful to extract or unpack a subset of samples from a wiff or wiff2 file. For example, if I want to send some "example data" to a collaborator or support, the entire file with 100 samples may be too large so would be excellent to extract a subset.

Also, sometimes (like for MS-DIAL), we need individual files and not multi-sample wiff/wiff2 files. Allowing an "unpack" function could help in these workflows.