Make default excludes apply to root only (#185)

* Make default excludes apply to root only

* Fix reference error

Author: swhite24

lib/main.js

@@ -164,14 +164,14 @@ Lambda.prototype._zipfileTmpPath = function (program) {
 };
 
 Lambda.prototype._rsync = function (program, src, dest, excludeNodeModules, callback) {
-  var excludes = ['.git*', '*.swp', '.editorconfig', 'deploy.env', '*.log', 'build/'],
+  var excludes = ['.git*', '*.swp', '.editorconfig', 'deploy.env', '*.log', '/build/'],
       excludeGlobs = [];
   if (program.excludeGlobs) {
     excludeGlobs = program.excludeGlobs.split(' ');
   }
   var excludeArgs = excludeGlobs
     .concat(excludes)
-    .concat(excludeNodeModules ? ['node_modules'] : [])
+    .concat(excludeNodeModules ? ['/node_modules'] : [])
     .map(function (exclude) {
       return '--exclude=' + exclude;
     }).join(' ');