Remove trailing commas for IE 9 compatibility

Summary: IE 9 doesn't like trailing commas. When we introduced eslint, we added
a bunch of trailing commas, which makes IE 9 sad.

Test Plan:
 - `make lint`
 - Visit http://localhost:7936/ using IE 9 on browserstack.
 - See that the math loads, and there are no errors in the F12 developer tools.

@kevinb

dockers/Screenshotter/screenshotter.js

@@ -25,52 +25,52 @@ var opts = require("nomnom")
     .option("browser", {
         abbr: "b",
         "default": "firefox",
-        help: "Name of the browser to use",
+        help: "Name of the browser to use"
     })
     .option("container", {
         abbr: "c",
         type: "string",
-        help: "Name or ID of a running docker container to contact",
+        help: "Name or ID of a running docker container to contact"
     })
     .option("seleniumURL", {
         full: "selenium-url",
-        help: "Full URL of the Selenium web driver",
+        help: "Full URL of the Selenium web driver"
     })
     .option("seleniumIP", {
         full: "selenium-ip",
-        help: "IP address of the Selenium web driver",
+        help: "IP address of the Selenium web driver"
     })
     .option("seleniumPort", {
         full: "selenium-port",
         "default": 4444,
-        help: "Port number of the Selenium web driver",
+        help: "Port number of the Selenium web driver"
     })
     .option("katexURL", {
         full: "katex-url",
-        help: "Full URL of the KaTeX development server",
+        help: "Full URL of the KaTeX development server"
     })
     .option("katexIP", {
         full: "katex-ip",
-        help: "Full URL of the KaTeX development server",
+        help: "Full URL of the KaTeX development server"
     })
     .option("katexPort", {
         full: "katex-port",
-        help: "Port number of the KaTeX development server",
+        help: "Port number of the KaTeX development server"
     })
     .option("include", {
         abbr: "i",
-        help: "Comma-separated list of test cases to process",
+        help: "Comma-separated list of test cases to process"
     })
     .option("exclude", {
         abbr: "x",
-        help: "Comma-separated list of test cases to exclude",
+        help: "Comma-separated list of test cases to exclude"
     })
     .option("verify", {
         flag: true,
-        help: "Check whether screenshot matches current file content",
+        help: "Check whether screenshot matches current file content"
     })
     .option("wait", {
-        help: "Wait this many seconds between page load and screenshot",
+        help: "Wait this many seconds between page load and screenshot"
     })
     .parse();
 
@@ -208,7 +208,7 @@ function tryConnect() {
     }
     var sock = net.connect({
         host: seleniumIP,
-        port: +seleniumPort,
+        port: +seleniumPort
     });
     sock.on("connect", function() {
         sock.end();
@@ -278,7 +278,7 @@ function imageDimensions(img) {
     return {
         buf: buf,
         width: buf.readUInt32BE(16),
-        height: buf.readUInt32BE(20),
+        height: buf.readUInt32BE(20)
     };
 }
 
@@ -399,7 +399,7 @@ function takeScreenshot(key) {
             }
         }
         var opt = new jspngopt.Optimizer({
-            pako: pako,
+            pako: pako
         });
         var buf = opt.bufferSync(img.buf);
         if (loadExpected) {

dockers/texcmp/texcmp.js

@@ -48,7 +48,7 @@ Q.all([
     readFile(path.join(ssDir, "test.tex"), "utf-8"),
     ensureDir(tmpDir),
     ensureDir(teximgDir),
-    ensureDir(diffDir),
+    ensureDir(diffDir)
 ]).spread(function(data) {
     template = data;
     // dirs have been created, template has been read, now rasterize.
@@ -79,14 +79,14 @@ function processTestCase(key) {
     var fftLatex = writeFile(texFile, tex).then(function() {
         // Step 2: call "pdflatex key" to create key.pdf
         return execFile("pdflatex", [
-            "-interaction", "nonstopmode", key,
+            "-interaction", "nonstopmode", key
         ], {cwd: tmpDir});
     }).then(function() {
         console.log("Typeset " + key);
         // Step 3: call "convert ... key.pdf key.png" to create key.png
         return execFile("convert", [
             "-density", dpi, "-units", "PixelsPerInch", "-flatten",
-            "-depth", "8", pdfFile, pngFile,
+            "-depth", "8", pdfFile, pngFile
         ]);
     }).then(function() {
         console.log("Rasterized " + key);
@@ -167,7 +167,7 @@ function processTestCase(key) {
             // First image is red, second green, third blue channel of result
             "-channel", "RGB", "-combine",
             "-trim",  // remove everything with the same color as the corners
-            diffFile, // output file name
+            diffFile // output file name
         ]);
     }).then(function() {
         console.log("Compared " + key);
@@ -244,7 +244,7 @@ function fftImage(image) {
         real: real,
         imag: imag,
         width: image.width,
-        height: image.height,
+        height: image.height
     };
 }