Use type for issue state

	* src/main/scala/codecheck/github/models/Issue.scala (state): Use
	IssueState.fromString to lift type from string.

	* src/main/scala/codecheck/github/models/PullRequest.scala
	(state): IssueState.fromString to lift type from string.

Author: ashawley

src/main/scala/codecheck/github/models/Issue.scala

@@ -172,7 +172,7 @@ case class Issue(value: JValue) extends AbstractJson(value) {
     case _ => Nil
   }
 
-  def state = get("state")
+  def state = IssueState.fromString(get("state"))
   def locked = boolean("locked")
 
   lazy val assignee = objectOpt("assignee")(v => User(v))

src/main/scala/codecheck/github/models/PullRequest.scala

@@ -57,7 +57,7 @@ case class PullRequestRef(value: JValue) extends AbstractJson(value) {
 case class PullRequest(value: JValue) extends AbstractJson(value) {
   def number = get("number").toLong
   def body = get("body")
-  def state = get("state")
+  def state = IssueState.fromString(get("state"))
   def title = get("title")
   lazy val head = PullRequestRef(value \ "head")
   lazy val base = PullRequestRef(value \ "base")