Fix lu deprecation warning on julia v1.7+

[dkarrasch]

I'm not sure why you had the InteractiveUtils subtype method imported. I found no use of it in the package, so I removed that dependency. I also bumped the patch version. If you don't like any of those "extra" edits, no problem, I'll revert them if preferred.

[coveralls]

Coverage decreased (-53.3%) to 42.805% when pulling 7a70ae3 on dkarrasch:dk/lufix into f2e4c83 on JuliaDiff:master.

[lbenet]

Thanks a lot for cleaning this as well as solving #281!

Regarding InteractiveUtils, I guess it was a leftover of some experiments... I was trying to distinguish types which are Number but not AbstractSeries, which i named NumberNotSeries, from the universe of Number; my idea was to do this dynamically. But it did not worked out when other packages were loaded (say ModelingToolKit.jl); see #242. So now NumberNotSeries is simply the union of Real and Complex.

[lbenet]

Anyway, I'm merging, and tag the new version. Thanks a lot!