feat: replace shell script with python implementation

- add requirements.txt
- allow disabling a stack
- update config example
- update README

config.yml.example

@@ -0,0 +1,11 @@
+stacks:
+  - dir: /path/to/first-repo
+  - dir: /path/to/second-repo
+    compose-files:
+      - docker-compose-dev.yml
+  - dir: /path/to/third-repo
+    compose-files:
+      - subdirA/docker-compose.yml
+      - subdirB/docker-compose.yml
+  - dir: /path/to/fourth-repo
+    enabled: false