added some readme, changed Schema#validate() visibility to public

Author: erosb

README.md

@@ -1,4 +1,21 @@
-<img src="https://travis-ci.org/erosb/json-schema-validator.svg?branch=master" />
-
 JSON Schema Validator
+=====================
+
+This project is an implementation of the [JSON Schema Core Draft v4]("http://json-schema.org/latest/json-schema-core.html") specification.
+It uses the [org.json API]("http://www.json.org/java/") for representing JSON data.
+
+Quickstart
+----------
+
+```java
+import org.everit.jsonvalidator.Schema;
+import org.everit.jsonvalidator.loader.SchemaLoader;
+import org.json.JSONObject;
+import org.json.JSONTokener;
+// ...
+JSONObject rawSchema = new JSONObject(new JSONTokener(Main.class.getResourceAsStream("/path/to/your/schema.json")));
+Schema schema = SchemaLoader.load(rawSchema);
+schema.validate(new JSONObject("{\"hello\" : \"world\"}")); // throws a ValidationException if this object is invalid
+```
+
 

core/src/main/java/org/everit/jsonvalidator/ReferenceSchema.java

@@ -53,7 +53,7 @@ public ReferenceSchema(final Builder builder) {
   }
 
   @Override
-  void validate(final Object subject) {
+  public void validate(final Object subject) {
     if (referredSchema == null) {
       throw new IllegalStateException("referredSchema must be injected before validation");
     }

core/src/main/java/org/everit/jsonvalidator/Schema.java

@@ -75,7 +75,7 @@ protected Schema(final Builder builder) {
   /**
    * Validates.
    */
-  abstract void validate(final Object subject);
+  public abstract void validate(final Object subject);
 
   @Override
   public int hashCode() {