feat: deprecate request and implement axios. bump ws. cleaning. expose request options for proxy support. resolves #12. resolves #4.

lib/util/requestUtils.js

@@ -0,0 +1,21 @@
+const { createHmac } = require('crypto');
+
+module.exports = {
+  signMessage(message, secret) {
+    return createHmac('sha256', secret)
+      .update(message)
+      .digest('hex');
+  },
+  serializeParams(params, strict_validation) {
+    return Object.keys(params)
+      .sort()
+      .map(key => {
+        const value = params[key];
+        if (strict_validation === true && typeof value === 'undefined') {
+          throw new Error('Failed to sign API request due to undefined parameter');
+        }
+        return `${key}=${value}`;
+      })
+      .join('&');
+  }
+};