Modify user agent (#187)

* Add additional fields for Runner.

The current model is missing some fields.

* Make the User-Agent settable.

This makes it easier to see which program executed requests.

src/main/java/org/gitlab/api/GitlabAPI.java

@@ -48,6 +48,7 @@ public class GitlabAPI {
     private AuthMethod authMethod;
     private boolean ignoreCertificateErrors = false;
     private int requestTimeout = 0;
+    private String userAgent = GitlabAPI.class.getCanonicalName() + "/" + System.getProperty("java.version");
 
     private GitlabAPI(String hostUrl, String apiToken, TokenType tokenType, AuthMethod method) {
         this.hostUrl = hostUrl.endsWith("/") ? hostUrl.replaceAll("/$", "") : hostUrl;
@@ -2482,4 +2483,17 @@ public class GitlabAPI {
        projects = Arrays.asList(response);
        return projects;
    }
+
+    /**
+     * Set the User-Agent header for the requests.
+     *
+     * @param userAgent
+     */
+    public void setUserAgent(String userAgent) {
+        this.userAgent = userAgent;
+    }
+
+    public String getUserAgent() {
+        return userAgent;
+    }
 }

src/main/java/org/gitlab/api/http/GitlabHTTPRequestor.java

@@ -380,7 +380,7 @@ public class GitlabHTTPRequestor {
                 throw (IOException) new IOException("Failed to set the custom verb").initCause(x);
             }
         }
-
+        connection.setRequestProperty("User-Agent", root.getUserAgent());
         connection.setRequestProperty("Accept-Encoding", "gzip");
         return connection;
     }