Fix bug in length of BlockedUnitRange with non-1 start

[dlfivefifty]

No description provided.

[codecov]

Codecov Report

Merging #167 (260a2ae) into master (0303eaf) will not change coverage.
The diff coverage is 100.00%.

@@           Coverage Diff           @@
##           master     #167   +/-   ##
=======================================
  Coverage   91.13%   91.13%           
=======================================
  Files          15       15           
  Lines        1230     1230           
=======================================
  Hits         1121     1121           
  Misses        109      109           

Impacted Files	Coverage Δ
src/blockaxis.jl	96.58% <100.00%> (ø)

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