Updated Typos in devstack

(1/5) Updated HACKING.rst for typos
(2/5) Updated typos in lib/dlm
(3/5) Updated typos in lib/ironic
(4/5) Updated typos in unittest.sh
(5/5) Updated typos in test_meta_config.sh

Change-Id: I7aafa3af69df9dc6a5923a8557f380d48b73433a
diff --git a/lib/dlm b/lib/dlm
index f68ee26..95e9b0a 100644
--- a/lib/dlm
+++ b/lib/dlm
@@ -46,7 +46,7 @@
 # - cleanup_dlm
 
 # This should be declared in the settings file of any plugin or
-# service that needs to have a dlm in their enviroment.
+# service that needs to have a dlm in their environment.
 function use_dlm {
     enable_service $(dlm_backend)
 }
diff --git a/lib/ironic b/lib/ironic
index 016e639..6a32983 100644
--- a/lib/ironic
+++ b/lib/ironic
@@ -92,7 +92,7 @@
 # Use DIB to create deploy ramdisk and kernel.
 IRONIC_BUILD_DEPLOY_RAMDISK=$(trueorfalse True IRONIC_BUILD_DEPLOY_RAMDISK)
 # If not use DIB, these files are used as deploy ramdisk/kernel.
-# (The value must be a absolute path)
+# (The value must be an absolute path)
 IRONIC_DEPLOY_RAMDISK=${IRONIC_DEPLOY_RAMDISK:-}
 IRONIC_DEPLOY_KERNEL=${IRONIC_DEPLOY_KERNEL:-}
 IRONIC_DEPLOY_ELEMENT=${IRONIC_DEPLOY_ELEMENT:-deploy-ironic}
@@ -672,7 +672,7 @@
     # enable tftp natting for allowing connections to HOST_IP's tftp server
     sudo modprobe nf_conntrack_tftp
     sudo modprobe nf_nat_tftp
-    # explicitly allow DHCP - packets are occassionally being dropped here
+    # explicitly allow DHCP - packets are occasionally being dropped here
     sudo iptables -I INPUT -p udp --dport 67:68 --sport 67:68 -j ACCEPT || true
     # nodes boot from TFTP and callback to the API server listening on $HOST_IP
     sudo iptables -I INPUT -d $HOST_IP -p udp --dport 69 -j ACCEPT || true