Sniff den_fmt files where END header is on one line

[patrick-austin]

sniff_prefix for the CASTEP den_fmt datatype checks for a particular phrase to appear in the file header. However, in files generated with more recent versions of CASTEP, this phrase appears on one single line whereas before it was split over two lines.

To correctly sniff all versions of the file, concat the two possible lines the phrase can be spread over and remove whitespace/newlines and compare using that.

How to test the changes?

(Select all options that apply)

• I've included appropriate automated tests.
  • Added new test file with the "one line" END header: ...
• This is a refactoring of components with existing test coverage.
  • Existing tests with Si.den_fmt and YbCuAs2.den_fmt should still pass
• Instructions for manual testing are as follows:

License

• I agree to license these and all my past contributions to the core galaxy codebase under the MIT license.