Created the managarr-demo repository and created a Dockerfile for CI/CD builds. Added Docker sections to the README as well

Makefile

@@ -1,4 +1,7 @@
 #!make
+VERSION  := latest
+IMG_NAME := darkalex17/managarr
+IMAGE    := ${IMG_NAME}:${VERSION}
 
 default: run
 
@@ -14,6 +17,9 @@ test-cov:
 build: test
 	@cargo build --release
 
+docker:
+	@DOCKER_BUILDKIT=1 docker build --rm -t ${IMAGE} .
+
 run:
 	@CARGO_INCREMENTAL=1 cargo fmt && make lint && cargo run
 
@@ -34,4 +40,5 @@ release:
 	@git tag -a ${V} -m "Release ${V}" && git push origin ${V}
 
 delete-tag:
-	@git tag -d ${V} && git push --delete origin ${V}
+	@git tag -d ${V} && git push --delete origin ${V}
+