Create devcontainer and fix build

The container doesn't contain all dependencies yet, but runs the first problems!

Author: stoman

.devcontainer/devcontainer.json

@@ -0,0 +1,40 @@
+// For format details, see https://aka.ms/devcontainer.json. For config options, see the
+// README at: https://github.com/devcontainers/templates/tree/main/src/rust
+{
+	"name": "Compretitive Programming",
+	// Or use a Dockerfile or Docker Compose file. More info: https://containers.dev/guide/dockerfile
+	"image": "mcr.microsoft.com/devcontainers/rust:1-1-bullseye",
+	// Full list: https://containers.dev/features
+	"features": {
+		"ghcr.io/devcontainers/features/git:1": {},
+		"ghcr.io/jungaretti/features/make:1": {},
+		"ghcr.io/devcontainers/features/java:1": {},
+		"ghcr.io/devcontainers-extra/features/kotlin-sdkman:2": {},
+		"ghcr.io/devcontainers/features/python:1": {}
+	},
+
+	// Use 'mounts' to make the cargo cache persistent in a Docker Volume.
+	// "mounts": [
+	// 	{
+	// 		"source": "devcontainer-cargo-cache-${devcontainerId}",
+	// 		"target": "/usr/local/cargo",
+	// 		"type": "volume"
+	// 	}
+	// ]
+
+	// Use 'forwardPorts' to make a list of ports inside the container available locally.
+	// "forwardPorts": [],
+
+	// Use 'postCreateCommand' to run commands after the container is created.
+	"postCreateCommand": {
+		"rust version": "rustc --version",
+		"link rust": "sudo ln -s /usr/local/cargo/bin/rustc /usr/bin/rustc",
+		"problemtools": "sudo apt-get update && sudo apt-get install -y libboost-all-dev && pip install git+https://github.com/kattis/problemtools@master"
+	}
+
+	// Configure tool-specific properties.
+	// "customizations": {},
+
+	// Uncomment to connect as root instead. More info: https://aka.ms/dev-containers-non-root.
+	// "remoteUser": "root"
+}

problems/Makefile

@@ -5,4 +5,4 @@ all: $(PROBLEMS)
 .PHONY: all $(PROBLEMS)
 
 $(PROBLEMS): 
-	verifyproblem -p config submissions $@
+	verifyproblem -p config submissions -- $@