Update readme, use more threads on build

Signed-off-by: didinst <9f6129a2ddff0d0c6d03169eaa75e3fea1c1770f>

Dockerfile

@@ -1,12 +1,14 @@
 FROM alpine:latest
-RUN apk add --no-cache openssl-dev linux-headers zlib-dev gcc gperf cmake build-base git libstdc++ \
+RUN apk update && apk --no-cache upgrade \
+	&& apk add --no-cache openssl-dev linux-headers zlib-dev gcc gperf cmake build-base git libstdc++ \
 	&& git clone --recursive https://github.com/tdlib/telegram-bot-api.git \
 	&& cd telegram-bot-api \
 	&& mkdir build \
 	&& cd build \
 	&&	cmake -DCMAKE_BUILD_TYPE=Release .. \
-	&& cmake --build . -j 4 --target install \
+	&& cmake --build . -j 8 --target install \
 	&& apk del linux-headers gcc gperf cmake build-base git \
+	&& cd ../.. \
 	&& rm -r ./telegram-bot-api
 RUN adduser --no-create-home --uid 2000 --disabled-password tg-bot \
 	&& mkdir -p /opt/telegram-bot-api \

README.md

@@ -18,6 +18,10 @@ Or build manualy: `docker build -t <you image name> .`
 And run it: 
     `docker run -p <host port>:8081 --name <you container name> --env-file=./tg-bot-api.env <you image name>`
 
+## This image on dockerhub
+
+Built for linux OS amd64 and arm/v7 arch https://hub.docker.com/r/bearns/tg-bot-api-server
+
 ## Crossbuild
 
 Use qemu and buildx if you need it.
@@ -27,8 +31,6 @@ Get buidlx here https://github.com/docker/buildx
 Buildix documentation here https://docs.docker.com/buildx/working-with-buildx/
 
 Run image
-`docker run --privileged --rm docker/binfmt`
-Or (alternative)
 `docker run --privileged --rm  multiarch/qemu-user-static:latest`
 
 Create profile (linux/arm/v7 used as example)