Enable sending CORS headers from electrs backend in startup script

Fixes #367

production/electrs-start-liquid

@@ -12,6 +12,7 @@ do
 		-- \
 		-vvv \
 		--address-search \
+		--cors '*' \
 		--network liquid \
 		--daemon-dir /elements \
 		--http-addr '[::]:3001' \

production/electrs-start-mainnet

@@ -11,6 +11,7 @@ do
 		-- \
 		-vvvv \
 		--address-search \
+		--cors '*' \
 		--db-dir /electrs \
 		--daemon-dir $HOME \
 		--http-addr '[::]:3000' \

production/electrs-start-signet

@@ -11,6 +11,7 @@ do
 		-- \
 		-vv \
 		--network signet \
+		--cors '*' \
 		--db-dir /electrs \
 		--daemon-rpc-addr '127.0.0.1:38332' \
 		--daemon-dir /bitcoin \

production/electrs-start-testnet

@@ -11,6 +11,7 @@ do
 		-- \
 		-vvvv \
 		--network testnet \
+		--cors '*' \
 		--db-dir /electrs \
 		--daemon-dir $HOME \
 		--http-addr '[::]:3002' \