Initial revision of .lgtm.yml config file (#6258)

This allows for doing security code analysis via lgtm.com. This is just the first known good config I have tried that could successfully run a build. There are many options if we wish to exclude certain files/dir or other pre/post build options:
https://help.semmle.com/lgtm-enterprise/user/help/lgtm.yml-configuration-file.html

Author: ezelkow1

.lgtm.yml

@@ -0,0 +1,32 @@
+#  Licensed to the Apache Software Foundation (ASF) under one
+#  or more contributor license agreements.  See the NOTICE file
+#  distributed with this work for additional information
+#  regarding copyright ownership.  The ASF licenses this file
+#  to you under the Apache License, Version 2.0 (the
+#  "License"); you may not use this file except in compliance
+#  with the License.  You may obtain a copy of the License at
+#
+#  http://www.apache.org/licenses/LICENSE-2.0
+#
+#  Unless required by applicable law or agreed to in writing, software
+#  distributed under the License is distributed on an "AS IS" BASIS,
+#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+#  See the License for the specific language governing permissions and
+#  limitations under the License.
+
+
+extraction:
+  cpp:
+    prepare:
+      packages:
+      - "libcjose-dev"
+      - "libcjose0"
+      - "libjansson-dev"
+      - "libluajit-5.1-dev"
+      - "libpcre3-dev"
+      - "zlib1g-dev"
+    after_prepare: "autoreconf -fiv"
+    configure:
+      command: "./configure --enable-experimental-plugins"
+    index:
+      build_command: "make -j"