Remove jsnext:main from package.json.

This isn't worth the extra space that will come from having to
install the src/ folder in addition to lib/ on npm install.

Author: nwronski

package.json

@@ -14,7 +14,6 @@
     "ast"
   ],
   "main": "lib/index.js",
-  "jsnext:main": "src/index.js",
   "bin": {
     "sqlite-parser": "bin/sqlite-parser"
   },