Heap data structure and testing

[haotongwang]

Heap methods:

• isEmpty
• peek
• push
• getMax

Heap public properties:

• length

Testing includes tests for each method and property.

#118

[codecov-io]

Codecov Report

Merging #127 into master will increase coverage by 0.01%. The diff coverage is 100%.

@@            Coverage Diff             @@
##           master     #127      +/-   ##
==========================================
+ Coverage   99.66%   99.68%   +0.01%     
==========================================
  Files          39       40       +1     
  Lines         602      625      +23     
  Branches       88       94       +6     
==========================================
+ Hits          600      623      +23     
  Misses          2        2

Impacted Files	Coverage Δ
src/dataStructures/Heap.js	100% <100%> (ø)

---

Continue to review full report at Codecov.

Legend - Click here to learn more Δ = absolute <relative> (impact), ø = not affected, ? = missing data Powered by Codecov. Last update ff12899...4e347be. Read the comment docs.