Migrate to httpclient5

* Migrate imports, classes and methods
* Reduce usage of deprecated classes and methods
* Minor code cleanup

Author: strangelookingnerd

pom.xml

@@ -88,8 +88,8 @@ THE SOFTWARE.
 
 	<dependencies>
 		<dependency>
-			<groupId>org.jenkins-ci.plugins</groupId>
-			<artifactId>apache-httpcomponents-client-4-api</artifactId>
+			<groupId>io.jenkins.plugins</groupId>
+			<artifactId>apache-httpcomponents-client-5-api</artifactId>
 		</dependency>
 
 		<dependency>

src/main/java/jenkins/plugins/http_request/HttpMode.java

@@ -6,20 +6,20 @@
  * @author Janario Oliveira
  */
 public enum HttpMode {
-	GET,
-	HEAD,
-	POST,
-	PUT,
-	DELETE,
-	OPTIONS,
-	PATCH,
-	MKCOL;
+    GET,
+    HEAD,
+    POST,
+    PUT,
+    DELETE,
+    OPTIONS,
+    PATCH,
+    MKCOL;
 
-	public static ListBoxModel getFillItems() {
-		ListBoxModel items = new ListBoxModel();
-		for (HttpMode httpMode : values()) {
-			items.add(httpMode.name());
-		}
-		return items;
-	}
+    public static ListBoxModel getFillItems() {
+        ListBoxModel items = new ListBoxModel();
+        for (HttpMode httpMode : values()) {
+            items.add(httpMode.name());
+        }
+        return items;
+    }
 }