Add the linter name

With this messages are identified as coming from this linter, if the user chooses to do so in their linter UI.

Author: Arcanemagus

lib/index.js

@@ -11,6 +11,7 @@ export function activate() {
 
 export function provideLinter() {
   return {
+    name: 'JSON Lint',
     grammarScopes: ['source.json'],
     scope: 'file',
     lintOnFly: true,