a json format validation tool
##use case
doc_validate = jacob.define("doc", {
"name": String,
"tags": [String],
"comments": [String],
"author": {
"name": String,
"github": String
}
});
doc_validate({
"name": "jacob",
"tags": ["json", "validation"],
"comments": [],
"author": {"name": "mqli", "github": "github.com/mqli"}
});//true