Spatiallite3 provider implementation (#17)

* 	new file:   docker/Dockerfile
Dockerfile for pygeoapi

* 	modified:   pygeoapi/provider/__init__.py
	new file:   tests/data/ne_110m_lakes.sqlite
	new file:   tests/json_marshmallow.py
	new file:   tests/test_sqlite_provider.py

Sqlit implementation and testing marshmallows

* 	new file:   provider/sqlite.py
	new file:   provider/tmp_parser.py
Sqlite provider

* Testing sqlalchemy

* query for sqlite3

* Countries dataset, message in assert

* yml config

* table in data link and query implemented without limit

* PR of refactor

* functional sqlite3 driver

* flake8

* pipreq for complete list of requirements

* updated readme with working examples, extra requirements

* typos, SQLite removed Dockerfile and ne_100m_lakes.sqlite

* update requirements

* pypandoc in requirements-dev.txt

tests/test_sqlite_provider.py

@@ -0,0 +1,37 @@
+# Needs to be run like: pytest -s test_sqlite_provider.py
+# In eclipse we need to set PYGEOAPI_CONFIG, Run>Debug Configurations>
+# (Arguments as py.test and set external variables to the correct config path)
+
+import pytest
+from pygeoapi.provider.sqlite import SQLiteProvider
+
+
+@pytest.fixture()
+def config():
+    return {
+            'name': 'Sqlite',
+            'data': './tests/data/ne_110m_admin_0_countries.sqlite',
+            'id_field': "ogc_fid",
+            'table': 'ne_110m_admin_0_countries'}
+
+
+def test_query(config):
+    """Testing query for a valid JSON object with geometry"""
+
+    p = SQLiteProvider(config)
+    feature_collection = p.query()
+    assert feature_collection.get('type', None) == "FeatureCollection"
+    features = feature_collection.get('features', None)
+    assert features is not None
+    feature = features[0]
+    properties = feature.get("properties", None)
+    assert properties is not None
+    geometry = feature.get("geometry", None)
+    assert geometry is not None
+
+
+def test_get(config):
+    p = SQLiteProvider(config)
+    results = p.get(118)
+    assert len(results['features']) == 1
+    assert "Netherlands" in results['features'][0]['properties']['admin']