Remove straggling references to Associative

[kmsquire]

Fixes #351.

[oxinabox]

Title is wrong, these changes are mostly to how markdown formatting styles are use.
With 1 or 2 removals of AbstractDict
But LGTM

[codecov]

Codecov Report

Merging #441 into master will increase coverage by 0.01%.
The diff coverage is n/a.

@@            Coverage Diff            @@
##           master    #441      +/-   ##
=========================================
+ Coverage   98.19%   98.2%   +0.01%     
=========================================
  Files          30      30              
  Lines        1658    1669      +11     
=========================================
+ Hits         1628    1639      +11     
  Misses         30      30

Impacted Files	Coverage Δ
src/circular_buffer.jl	100% <0%> (ø)	⬆️

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[scls19fr]

Thanks @kmsquire

[kmsquire]

Title is wrong, these changes are mostly to how markdown formatting styles are use.
With 1 or 2 removals of AbstractDict

Sorry, I had auto formatting on save turned on, and didn’t pay attention to the diff uploaded. Whoops! The only changes I consciously made were the ones related to the title.