Cleaned up imports.

src/main/java/org/gitlab4j/api/CommitsApi.java

@@ -2,7 +2,6 @@ package org.gitlab4j.api;
 
 import java.util.List;
 
-import javax.ws.rs.core.Form;
 import javax.ws.rs.core.GenericType;
 import javax.ws.rs.core.Response;
 

src/main/java/org/gitlab4j/api/GitLabApi.java

@@ -2,10 +2,8 @@ package org.gitlab4j.api;
 
 import java.util.Map;
 
-import javax.ws.rs.core.MultivaluedMap;
 import javax.ws.rs.core.Response;
 
-import org.gitlab4j.api.models.Group;
 import org.gitlab4j.api.models.Session;
 import org.gitlab4j.api.models.Version;