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/brocade b/lib/neutron_plugins/brocade
index 8e18d04..4443fa7 100644
--- a/lib/neutron_plugins/brocade
+++ b/lib/neutron_plugins/brocade
@@ -5,53 +5,53 @@
 BRCD_XTRACE=$(set +o | grep xtrace)
 set +o xtrace
 
-function is_neutron_ovs_base_plugin() {
+function is_neutron_ovs_base_plugin {
     return 1
 }
 
-function neutron_plugin_create_nova_conf() {
+function neutron_plugin_create_nova_conf {
     NOVA_VIF_DRIVER=${NOVA_VIF_DRIVER:-"nova.virt.libvirt.vif.LibvirtGenericVIFDriver"}
 }
 
-function neutron_plugin_install_agent_packages() {
+function neutron_plugin_install_agent_packages {
     install_package bridge-utils
 }
 
-function neutron_plugin_configure_common() {
+function neutron_plugin_configure_common {
     Q_PLUGIN_CONF_PATH=etc/neutron/plugins/brocade
     Q_PLUGIN_CONF_FILENAME=brocade.ini
     Q_DB_NAME="brcd_neutron"
     Q_PLUGIN_CLASS="neutron.plugins.brocade.NeutronPlugin.BrocadePluginV2"
 }
 
-function neutron_plugin_configure_debug_command() {
+function neutron_plugin_configure_debug_command {
     iniset $NEUTRON_TEST_CONFIG_FILE DEFAULT external_network_bridge
 }
 
-function neutron_plugin_configure_dhcp_agent() {
+function neutron_plugin_configure_dhcp_agent {
     iniset $Q_DHCP_CONF_FILE DEFAULT dhcp_agent_manager neutron.agent.dhcp_agent.DhcpAgentWithStateReport
 }
 
-function neutron_plugin_configure_l3_agent() {
+function neutron_plugin_configure_l3_agent {
     iniset $Q_L3_CONF_FILE DEFAULT external_network_bridge
     iniset $Q_L3_CONF_FILE DEFAULT l3_agent_manager neutron.agent.l3_agent.L3NATAgentWithStateReport
 }
 
-function neutron_plugin_configure_plugin_agent() {
+function neutron_plugin_configure_plugin_agent {
     AGENT_BINARY="$NEUTRON_BIN_DIR/neutron-linuxbridge-agent"
 }
 
-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.BridgeInterfaceDriver
 }
 
-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
 }