add NPM pkg for .sol syntax hilighting

package.json

@@ -3,6 +3,7 @@
   "version": "v0.6.4",
   "description": "Minimalistic browser-based Solidity IDE",
   "devDependencies": {
+    "ace-mode-solidity": "^0.1.0",
     "async": "^2.1.2",
     "babel-eslint": "^7.1.1",
     "babel-plugin-transform-object-assign": "^6.22.0",

src/app/editor/editor.js

@@ -13,7 +13,7 @@ var Range = ace.acequire('ace/range').Range
 require('brace/ext/language_tools')
 require('brace/ext/searchbox')
 var langTools = ace.acequire('ace/ext/language_tools')
-require('./mode-solidity.js')
+require('ace-mode-solidity/build/remix-ide/mode-solidity')
 var styleGuide = require('../ui/styles-guide/theme-chooser')
 var styles = styleGuide.chooser()
 
@@ -143,7 +143,7 @@ function Editor (opts = {}, localRegistry) {
   }
 
   function createSession (content) {
-    var s = new ace.EditSession(content, 'ace/mode/javascript')
+    var s = new ace.EditSession(content, 'ace/mode/solidity')
     s.setUndoManager(new ace.UndoManager())
     s.setTabSize(4)
     s.setUseSoftTabs(true)