fixing hue and saturation examples closes #401

Author: Lauren McCarthy

src/data/examples/en/07_Color/00_Hue.js

@@ -5,7 +5,7 @@
  * yellow, etc.) Move the cursor vertically over each bar to alter its hue.
  */
 const barWidth = 20;
-const lastBar = -1;
+let lastBar = -1;
 
 function setup() {
   createCanvas(720, 400);

src/data/examples/en/07_Color/01_Saturation.js

@@ -6,7 +6,7 @@
  * Move the cursor vertically over each bar to alter its saturation.
  */
 const barWidth = 20;
-const lastBar = -1;
+let lastBar = -1;
 
 function setup() {
   createCanvas(720, 400);

src/data/examples/es/07_Color/00_Hue.js

@@ -6,7 +6,7 @@
  * Mueve el cursor verticalmente sobre cada barra para alterar su tinte.
  */
 const barWidth = 20;
-const lastBar = -1;
+let lastBar = -1;
 
 function setup() {
   createCanvas(720, 400);

src/data/examples/es/07_Color/01_Saturation.js

@@ -6,7 +6,7 @@
  * Mueve el cursor verticalmente sobre cada barra para alterar su saturación.
  */
 const barWidth = 20;
-const lastBar = -1;
+let lastBar = -1;
 
 function setup() {
   createCanvas(720, 400);

src/data/examples/zh-Hans/07_Color/00_Hue.js

@@ -5,7 +5,7 @@
  * yellow, etc.) Move the cursor vertically over each bar to alter its hue.
  */
 const barWidth = 20;
-const lastBar = -1;
+let lastBar = -1;
 
 function setup() {
   createCanvas(720, 400);

src/data/examples/zh-Hans/07_Color/01_Saturation.js

@@ -6,7 +6,7 @@
  * Move the cursor vertically over each bar to alter its saturation.
  */
 const barWidth = 20;
-const lastBar = -1;
+let lastBar = -1;
 
 function setup() {
   createCanvas(720, 400);