Add docker-build task and update .gitignore

.gitignore

@@ -5,7 +5,7 @@ pastebin.txt
 .DS_Store
 test*.py
 docker-*
-.vscode
+.vscode/settings.json
 
 
 # Byte-compiled / optimized / DLL files

.vscode/tasks.json

@@ -0,0 +1,15 @@
+{
+    "version": "2.0.0",
+    "tasks": [
+        {
+            "label": "Docker: Build Image",
+            "type": "docker-build",
+            "platform": "python",
+            "dockerBuild": {
+                "context": "${workspaceFolder}",
+                "dockerfile": "${workspaceFolder}/Dockerfile",
+                "tag": "post-it:dev"
+            }
+        }
+    ]
+}