Update UserApi.java (#582)

Added theme_id and color_scheme_id properties.

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

@@ -974,6 +974,8 @@ public class UserApi extends AbstractApi {
                 .withParam("bio", user.getBio(), false)
                 .withParam("location", user.getLocation(), false)
                 .withParam("admin", user.getIsAdmin(), false)
+                .withParam("theme_id", user.getThemeId(), false)
+                .withParam("color_scheme_id", user.getColorSchemeId(), false)
                 .withParam("can_create_group", user.getCanCreateGroup(), false)
                 .withParam(skipConfirmationFeildName, user.getSkipConfirmation(), false)
                 .withParam("external", user.getExternal(), false)