Faster WKT Parser

[halfabrane]

Scala's parser combinators while elegant are not fast enough for parsing, especially when used in tight loops. Replacing with fast parse which is closer to hand implemented parsing while retaining the readability and extensibility of a parser combinator.

[codecov-io]

Codecov Report

Merging #117 into master will increase coverage by 0.17%.
The diff coverage is 96.42%.

@@            Coverage Diff             @@
##           master     #117      +/-   ##
==========================================
+ Coverage   76.71%   76.89%   +0.17%     
==========================================
  Files          42       42              
  Lines        1396     1402       +6     
  Branches      103       98       -5     
==========================================
+ Hits         1071     1078       +7     
+ Misses        325      324       -1

Impacted Files	Coverage Δ
...rc/main/scala/org/apache/spark/sql/types/WKT.scala	100% <100%> (ø)	⬆️
src/main/scala/magellan/WKTParser.scala	97.36% <96.29%> (+3.61%)	⬆️

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