Actually return value in dbapi method (#95)

The dbapi method should return the value that import_dbapi returns.
The original error from #91 and #92.

Fixes: #94

Author: potiuk

setup.py

@@ -29,7 +29,7 @@
     long_description = f.read()
 
 setup(name='sqlalchemy_drill',
-      version='1.1.7',
+      version='1.1.8',
       description="Apache Drill for SQLAlchemy",
       long_description=long_description,
       long_description_content_type="text/markdown",
@@ -64,7 +64,7 @@
       license='MIT',
       url='https://github.com/JohnOmernik/sqlalchemy-drill',
       download_url='https://github.com/JohnOmernik/sqlalchemy-drill/archive/'
-      '1.1.6.tar.gz',
+      '1.1.8.tar.gz',
       packages=find_packages(),
       include_package_data=True,
       tests_require=['nose >= 0.11'],

sqlalchemy_drill/__init__.py

@@ -19,7 +19,7 @@
 # OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
 # DEALINGS IN THE SOFTWARE.
 
-__version__ = '1.1.7'
+__version__ = '1.1.8'
 from sqlalchemy.dialects import registry
 
 registry.register("drill", "sqlalchemy_drill.sadrill", "DrillDialect_sadrill")

sqlalchemy_drill/sadrill.py

@@ -71,7 +71,7 @@ def import_dbapi(cls):
     @classmethod
     def dbapi(cls):
         """Deprecated in SQLAlchemy, retained for backwards compatibility."""
-        DrillDialect_sadrill.import_dbapi()
+        return DrillDialect_sadrill.import_dbapi()
 
     def create_connect_args(self, url, **kwargs):
         url_port = url.port or 8047