Added file.monitor backend [closes #172]

The file.monitor backend leverages watchdog instead of the Linux-only
inotify API and it replaces the inotify backend.

docs/source/backends.rst

@@ -22,6 +22,7 @@ Backends
     platypush/backend/clipboard.rst
     platypush/backend/covid19.rst
     platypush/backend/dbus.rst
+    platypush/backend/file.monitor.rst
     platypush/backend/foursquare.rst
     platypush/backend/github.rst
     platypush/backend/google.fit.rst

docs/source/conf.py

@@ -23,7 +23,7 @@ import sys
 # -- Project information -----------------------------------------------------
 
 project = 'platypush'
-copyright = '2017-2020, Fabio Manganiello'
+copyright = '2017-2021, Fabio Manganiello'
 author = 'Fabio Manganiello'
 
 # The short X.Y version
@@ -265,6 +265,7 @@ autodoc_mock_imports = ['googlesamples.assistant.grpc.audio_helpers',
                         'imapclient',
                         'pysmartthings',
                         'aiohttp',
+                        'watchdog',
                         ]
 
 sys.path.insert(0, os.path.abspath('../..'))

docs/source/events.rst

@@ -18,6 +18,7 @@ Events
     platypush/events/covid19.rst
     platypush/events/custom.rst
     platypush/events/distance.rst
+    platypush/events/file.rst
     platypush/events/foursquare.rst
     platypush/events/geo.rst
     platypush/events/github.rst

docs/source/platypush/backend/file.monitor.rst

@@ -0,0 +1,5 @@
+``platypush.backend.file.monitor``
+==================================
+
+.. automodule:: platypush.backend.file.monitor
+    :members:

docs/source/platypush/events/file.rst

@@ -0,0 +1,5 @@
+``platypush.message.event.file``
+================================
+
+.. automodule:: platypush.message.event.file
+    :members: