Merge of PR cozmo#148: Fix "onlyInvert" inversionAttempts option

Squashed commit of the following:

commit e7f282a
Author: LakeGH <lake@peardeck.com>
Date:   Thu Nov 14 13:29:15 2019 -0500

    Removing unneeded whitespace.

commit 13843e5
Author: LakeGH <lake@peardeck.com>
Date:   Thu Nov 14 13:14:50 2019 -0500

    Remove trailing whitespace for tslint

commit 4f3fef8
Author: LakeGH <lake@peardeck.com>
Date:   Thu Nov 14 13:12:12 2019 -0500

    Change order of inversionAttempts check for tslint

commit 0dfc578
Author: LakeGH <lake@peardeck.com>
Date:   Thu Nov 14 12:55:55 2019 -0500

    Fix "onlyInvert" inversionAttempts option.

    `shouldInvert` should also be true if `options.inversionAttempts` equals "onlyInvert".

src/index.ts

@@ -90,8 +90,8 @@ function jsQR(data: Uint8ClampedArray, width: number, height: number, providedOp
   mergeObject(options, defaultOptions);
   mergeObject(options, providedOptions);
 
-  const shouldInvert = options.inversionAttempts === "attemptBoth" || options.inversionAttempts === "invertFirst";
   const tryInvertedFirst = options.inversionAttempts === "onlyInvert" || options.inversionAttempts === "invertFirst";
+  const shouldInvert = options.inversionAttempts === "attemptBoth" || tryInvertedFirst;
   const {binarized, inverted} = binarize(data, width, height, shouldInvert, options.greyScaleWeights,
       options.canOverwriteImage);
   let result = scan(tryInvertedFirst ? inverted : binarized);