Give index information to BoundsError in getindex for splines

[DanielVandH]

BoundsError() throws an uninformative error - just BoundsError without any axis or index information. This adds that information. This also adds a @boundscheck.

[dlfivefifty]

You should be able to merge this youeself once tests pass?

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 90.47%. Comparing base (171465a) to head (d243564).
Report is 3 commits behind head on master.

Additional details and impacted files

@@             Coverage Diff             @@
##           master     #188       +/-   ##
===========================================
+ Coverage    0.00%   90.47%   +90.47%     
===========================================
  Files          11       11               
  Lines         768      819       +51     
===========================================
+ Hits            0      741      +741     
+ Misses        768       78      -690     

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[DanielVandH]

Hm, no I don't have the ability to.

[dlfivefifty]

I just added a maintain "role" . Can you do it now?

[DanielVandH]

Thanks!