Enforce function declaration format in bash8

Check that function calls look like ^function foo {$ in bash8, and fix
all existing failures of that check.  Add a note to HACKING.rst

Change-Id: Ic19eecb39e0b20273d1bcd551a42fe400d54e938
diff --git a/lib/neutron_plugins/ryu b/lib/neutron_plugins/ryu
index 334c227..9ae36d3 100644
--- a/lib/neutron_plugins/ryu
+++ b/lib/neutron_plugins/ryu
@@ -8,12 +8,12 @@
 source $TOP_DIR/lib/neutron_plugins/ovs_base
 source $TOP_DIR/lib/neutron_thirdparty/ryu      # for configuration value
 
-function neutron_plugin_create_nova_conf() {
+function neutron_plugin_create_nova_conf {
     _neutron_ovs_base_configure_nova_vif_driver
     iniset $NOVA_CONF DEFAULT libvirt_ovs_integration_bridge "$OVS_BRIDGE"
 }
 
-function neutron_plugin_install_agent_packages() {
+function neutron_plugin_install_agent_packages {
     _neutron_ovs_base_install_agent_packages
 
     # neutron_ryu_agent requires ryu module
@@ -22,28 +22,28 @@
     configure_ryu
 }
 
-function neutron_plugin_configure_common() {
+function neutron_plugin_configure_common {
     Q_PLUGIN_CONF_PATH=etc/neutron/plugins/ryu
     Q_PLUGIN_CONF_FILENAME=ryu.ini
     Q_DB_NAME="ovs_neutron"
     Q_PLUGIN_CLASS="neutron.plugins.ryu.ryu_neutron_plugin.RyuNeutronPluginV2"
 }
 
-function neutron_plugin_configure_debug_command() {
+function neutron_plugin_configure_debug_command {
     _neutron_ovs_base_configure_debug_command
     iniset $NEUTRON_TEST_CONFIG_FILE DEFAULT ryu_api_host $RYU_API_HOST:$RYU_API_PORT
 }
 
-function neutron_plugin_configure_dhcp_agent() {
+function neutron_plugin_configure_dhcp_agent {
     iniset $Q_DHCP_CONF_FILE DEFAULT ryu_api_host $RYU_API_HOST:$RYU_API_PORT
 }
 
-function neutron_plugin_configure_l3_agent() {
+function neutron_plugin_configure_l3_agent {
     iniset $Q_L3_CONF_FILE DEFAULT ryu_api_host $RYU_API_HOST:$RYU_API_PORT
     _neutron_ovs_base_configure_l3_agent
 }
 
-function neutron_plugin_configure_plugin_agent() {
+function neutron_plugin_configure_plugin_agent {
     # Set up integration bridge
     _neutron_ovs_base_setup_bridge $OVS_BRIDGE
     if [ -n "$RYU_INTERNAL_INTERFACE" ]; then
@@ -55,24 +55,24 @@
     _neutron_ovs_base_configure_firewall_driver
 }
 
-function neutron_plugin_configure_service() {
+function neutron_plugin_configure_service {
     iniset /$Q_PLUGIN_CONF_FILE ovs openflow_rest_api $RYU_API_HOST:$RYU_API_PORT
 
     _neutron_ovs_base_configure_firewall_driver
 }
 
-function neutron_plugin_setup_interface_driver() {
+function neutron_plugin_setup_interface_driver {
     local conf_file=$1
     iniset $conf_file DEFAULT interface_driver neutron.agent.linux.interface.OVSInterfaceDriver
     iniset $conf_file DEFAULT ovs_use_veth True
 }
 
-function has_neutron_plugin_security_group() {
+function has_neutron_plugin_security_group {
     # 0 means True here
     return 0
 }
 
-function neutron_plugin_check_adv_test_requirements() {
+function neutron_plugin_check_adv_test_requirements {
     is_service_enabled q-agt && is_service_enabled q-dhcp && return 0
 }