TS migration. #2288. (#2328)

* Added TS. Updated build and linting config. Added types.

* [ts-migrate][.] Rename files from JS/JSX to TS/TSX

Co-authored-by: ts-migrate <>

* [ts-migrate][.] Run TS Migrate

Co-authored-by: ts-migrate <>

* Corrected files mangled by ts-migrate.

* Updated lint config, minor linting.

* Re-enabled Husky.

* Updated tests and config.

* Reverted webpack devtool config.

* Removed obsolete snapshots.

* Added annotations snap.

* Updated tsconfig includes wrt linting.

* Removed ts-migrate.

Co-authored-by: Timmy Huang <tihuan@users.noreply.github.com>

client/src/components/brushableHistogram/footer.js

@@ -1,63 +0,0 @@
-import React from "react";
-
-const HistogramFooter = React.memo(
-  ({
-    displayName,
-    hideRanges,
-    rangeMin,
-    rangeMax,
-    rangeColorMin,
-    rangeColorMax,
-    isObs,
-    isGeneSetSummary,
-  }) => {
-    /*
-    Footer of each histogram.  Will render range and title.
-
-    Required props:
-      * displayName - the displayName, aka "n_genes", "FOXP2", etc.
-      * hideRanges - true/false, enables/disable rendering of ranges
-      * range - length two array, [min, max], containing the range values to display
-      * rangeColor - length two array, [mincolor, maxcolor], each a CSS color
-    */
-    return (
-      <div>
-        <div
-          style={{
-            display: "flex",
-            justifyContent: hideRanges ? "center" : "space-between",
-          }}
-        >
-          <span
-            style={{
-              color: rangeColorMin,
-              display: hideRanges ? "none" : "block",
-            }}
-          >
-            min {rangeMin.toPrecision(4)}
-          </span>
-          <span
-            data-testclass="brushable-histogram-field-name"
-            style={{ fontStyle: "italic" }}
-          >
-            {isObs && displayName}
-            {isGeneSetSummary && "gene set mean expression"}
-          </span>
-          <div style={{ display: hideRanges ? "block" : "none" }}>
-            : {rangeMin}
-          </div>
-          <span
-            style={{
-              color: rangeColorMax,
-              display: hideRanges ? "none" : "block",
-            }}
-          >
-            max {rangeMax.toPrecision(4)}
-          </span>
-        </div>
-      </div>
-    );
-  }
-);
-
-export default HistogramFooter;