Replace firstSeen with getFirstSeen

Author: oalders

src/main/java/com/maxmind/minfraud/response/Email.java

@@ -47,7 +47,7 @@ public Boolean isHighRisk() {
      *         ISO 8601 date format.
      */
     @JsonProperty("first_seen")
-    public String firstSeen() {
+    public String getFirstSeen() {
         return firstSeen;
     }
 }

src/test/java/com/maxmind/minfraud/response/EmailTest.java

@@ -25,6 +25,6 @@ public void testEmail() throws Exception {
 
         assertFalse(email.isFree());
         assertTrue(email.isHighRisk());
-        assertEquals(email.firstSeen(),"2017-01-02");
+        assertEquals(email.getFirstSeen(),"2017-01-02");
     }
 }