Change COLLECTD_DIR to COLLECTD_CEILOMTER_DIR

- change the name of the var used to store the
  collectd-ceilometer-plugin so that it doesn't conflict with
  OpenStack naming conventions later on.
- There is no end-user impact as this is set and used internally.

Closes-Bug #1603996

Change-Id: I5abd39a323aaddc66894e0a3ec3e475c0960d0dc

devstack/libs/collectd

@@ -36,7 +36,7 @@ cat << EOF | sudo tee $COLLECTD_CONF_DIR/collectd-ceilometer-plugin.conf
 </LoadPlugin>
 
 <Plugin python>
-    ModulePath "$COLLECTD_DIR"
+    ModulePath "$COLLECTD_CEILOMETER_DIR"
     LogTraces true
     Interactive false
     Import "collectd_ceilometer.plugin"

devstack/plugin.sh

@@ -2,7 +2,7 @@ local xtrace=$(set +o | grep xtrace)
 set -o xtrace
 
     # Initial source of lib script
-    source $COLLECTD_DIR/devstack/libs/collectd
+    source $COLLECTD_CEILOMETER_DIR/devstack/libs/collectd
 
     case $1 in
         "stack")

devstack/settings

@@ -1,5 +1,5 @@
 # General settings
-COLLECTD_DIR=$( cd "$( dirname "${BASH_SOURCE[0]}" )" && cd .. && pwd )
+COLLECTD_CEILOMETER_DIR=$( cd "$( dirname "${BASH_SOURCE[0]}" )" && cd .. && pwd )
 COLLECTD_BATCH_SIZE=${COLLECTD_BATCH_SIZE:-3}
 COLLECTD_INSTALL=${COLLECTD_INSTALL:-True}
 COLLECTD_CONF_DIR=${COLLECTD_CONF_DIR:-''}