Switch math command to expr-eval

package.json

@@ -1,6 +1,6 @@
 {
 	"name": "xiao",
-	"version": "123.6.1",
+	"version": "124.0.0",
 	"description": "Your personal server companion.",
 	"main": "Xiao.js",
 	"scripts": {
@@ -45,6 +45,7 @@
 		"discord.js-commando": "github:discordjs/Commando",
 		"dotenv": "^8.2.0",
 		"eslint": "^7.15.0",
+		"expr-eval": "^2.0.2",
 		"gifencoder": "^2.0.1",
 		"gm": "^1.23.1",
 		"html-entities": "^1.3.1",