Importing a set definition file removes spaces from source_file

[dlglin]

When importing a set definition file all spaces are removed from the source_file field. This causes issues if a pg file genuinely has spaces in the filename as the imported set will not have the correct source_file.

To reproduce:

1. Create a pg file with a space in the filename and add it to a set.
2. Export the set. The .def file will include the spaces in the filename.
3. Import the set into a course. The spaces have been removed from the filename, and the Set Detail page will report that the source file can't be found (unless there happens to be a file with same name with no spaces).

This looks to be done deliberately:

webwork2/lib/WeBWorK/File/SetDef.pm

Line 565 in 647d317

$problemData->{source_file} =~ s/\s*//g;

In earlier versions of WW there were problems with including spaces in filenames, but as far as I can tell everything else now works with them. Can this line be deleted, or might that break something else?

[drgrice1]

I think it should be okay. We will need to test it extensively though. So a pull request would be good now. Then it will be thoroughly tested by the next release, and any issues with doing so fixed.