Add Environment Variables to Docker template (#4012)

* Add disable registration as an environment variable

for docker

* Add REQUIRE_SIGNIN_VIEW as env var to docker

* Add variables to template

* Update docker docs

docker/etc/s6/gitea/setup

@@ -35,6 +35,8 @@ if [ ! -f /data/gitea/conf/app.ini ]; then
     DB_USER=${DB_USER:-"root"} \
     DB_PASSWD=${DB_PASSWD:-""} \
     INSTALL_LOCK=${INSTALL_LOCK:-"false"} \
+    DISABLE_REGISTRATION=${DISABLE_REGISTRATION:-"false"} \
+    REQUIRE_SIGNIN_VIEW=${REQUIRE_SIGNIN_VIEW:-"false"} \
     SECRET_KEY=${SECRET_KEY:-""} \
     envsubst < /etc/templates/app.ini > /data/gitea/conf/app.ini
 fi

docker/etc/templates/app.ini

@@ -38,3 +38,7 @@ ROOT_PATH = /data/gitea/log
 [security]
 INSTALL_LOCK = $INSTALL_LOCK
 SECRET_KEY   = $SECRET_KEY
+
+[service]
+DISABLE_REGISTRATION = $DISABLE_REGISTRATION
+REQUIRE_SIGNIN_VIEW  = $REQUIRE_SIGNIN_VIEW