Move nodes example into examples/ directory

Add a copyright header amd so on, and update the Sphinx examples file to
just source from the file.

Author: bootc

docs/examples.rst

@@ -1,15 +1,7 @@
 Examples
 ========
 
-Basic query for nodes using :mod:`pypuppetdb`::
+Basic query for nodes using :mod:`pypuppetdb`:
 
-   import pypuppetdb
-   import pypuppetdbquery
-
-   pdb = pypuppetdb.connect()
-
-   pdb_ast = pypuppetdbquery.parse(
-       '(processorcount=4 or processorcount=8) and kernel=Linux')
-
-   for node in pdb.nodes(query=pdb_ast):
-       print(node)
+.. literalinclude:: ../examples/nodes.py
+    :lines: 21-

examples/nodes.py

@@ -0,0 +1,30 @@
+# -*- coding: utf-8 -*-
+#
+# This file is part of pypuppetdbquery.
+# Copyright © 2016  Chris Boot <[email protected]>
+#
+# Licensed 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.
+"""
+Query for nodes using :mod:`pypuppetdb`.
+"""
+
+import pypuppetdb
+import pypuppetdbquery
+
+pdb = pypuppetdb.connect()
+
+pdb_ast = pypuppetdbquery.parse(
+    '(processorcount=4 or processorcount=8) and kernel=Linux')
+
+for node in pdb.nodes(query=pdb_ast):
+    print(node)