Single place for all the tink stack version

Tinkerbell is made of different components as we all know at this point.

Sandbox had those versions all over the places. This PR moves them as
part of the `envrc` file.

Signed-off-by: Gianluca Arbezzano <gianarb92@gmail.com>

deploy/docker-compose.yml

@@ -1,7 +1,7 @@
 version: "2.1"
 services:
   tink-server:
-    image: quay.io/tinkerbell/tink:sha-adb49da
+    image: ${TINKERBELL_TINK_SERVER_IMAGE}
     restart: unless-stopped
     environment:
       FACILITY: ${FACILITY:-onprem}
@@ -52,7 +52,7 @@ services:
       retries: 30
 
   tink-cli:
-    image: quay.io/tinkerbell/tink-cli:sha-adb49da
+    image: ${TINKERBELL_TINK_CLI_IMAGE}
     restart: unless-stopped
     environment:
       TINKERBELL_GRPC_AUTHORITY: 127.0.0.1:42113
@@ -89,7 +89,7 @@ services:
     network_mode: host
 
   boots:
-    image: quay.io/tinkerbell/boots:327-58ab49913b5498908b16e2607d265a61a05f73b6
+    image: ${TINKERBELL_TINK_BOOTS_IMAGE}
     restart: unless-stopped
     network_mode: host
     command: -dhcp-addr 0.0.0.0:67 -tftp-addr $TINKERBELL_HOST_IP:69 -http-addr $TINKERBELL_HOST_IP:80 -log-level DEBUG
@@ -133,7 +133,7 @@ services:
       - ./state/webroot:/usr/share/nginx/html/
 
   hegel:
-    image: quay.io/tinkerbell/hegel:196-fa897aa020769db8becb9be29adaeb6be92a7fc7
+    image: ${TINKERBELL_TINK_HEGEL_IMAGE}
     restart: unless-stopped
     network_mode: host
     environment:

deploy/vagrant/scripts/tinkerbell.sh

@@ -80,12 +80,12 @@ main() (
 		sudo apt-get install -y jq
 	fi
 
-	if [ ! -f ./envrc ]; then
-		./generate-envrc.sh eth1 >envrc
+	if [ ! -f ./.env ]; then
+		./generate-envrc.sh eth1 > .env
 	fi
 
 	# shellcheck disable=SC1091
-	. ./envrc
+	. ./.env
 
 	make_certs_writable