ci: add gitlab ci for docker compose

- split into multiple jobs
- specify tags for runner large
- use buildx and add separate builder default has no cache
- build image from cache and push to registry
- compose use tag and pull
- use cache tag for reuse
- https://github.com/moby/buildkit/issues/1981
- https://github.com/moby/buildkit/issues/3730
- use cache-to and cache-from with registry/cache
- add dockerignore to prevent rebuild on git changes
- use individual builders
- add step for docker compose up
- update readme
- update dockerignore
- add gitignore
- use script reduce duplicate code
- cache from and to in build, compose use cache
- dont push images just use cache
- build in compose step from cache
Signed-off-by: Lakshya Singh <lakshay.singh1108@gmail.com>

scripts/build_from_cache.sh

@@ -0,0 +1,8 @@
+#!/bin/sh
+
+set -ex
+
+SERVICE=$1
+
+cd $SERVICE
+docker build --load --builder $BUILDER --cache-from $CACHE/$SERVICE:$CACHE_TAG -t $SERVICE:$IMAGE_TAG .

scripts/build_image_cache.sh

@@ -0,0 +1,10 @@
+#!/bin/sh
+
+set -ex
+
+SERVICE=$1
+
+docker buildx create --name=$SERVICE --use
+cd $SERVICE
+
+docker build --load --builder=$SERVICE --cache-to type=registry,ref=$CACHE/$SERVICE:$CACHE_TAG --cache-from $CACHE/$SERVICE:$CACHE_TAG -t $SERVICE:$IMAGE_TAG .

scripts/pre-commit

@@ -0,0 +1,3 @@
+#!/usr/bin/sh
+
+cmp bitcoind/bitcoin.conf lightningd/bitcoin.conf