Fix spelling mistakes

git ls-files | misspellings -f -
Source: https://github.com/lyda/misspell-check

Change-Id: I7d63578734ca5cc1ec865a7d024c1a013d1ada87
diff --git a/exerciserc b/exerciserc
index c26ec2c..9105fe3 100644
--- a/exerciserc
+++ b/exerciserc
@@ -21,10 +21,10 @@
 # Max time to wait for a vm to terminate
 export TERMINATE_TIMEOUT=${TERMINATE_TIMEOUT:-30}
 
-# Max time to wait for a euca-volume command to propogate
+# Max time to wait for a euca-volume command to propagate
 export VOLUME_TIMEOUT=${VOLUME_TIMEOUT:-30}
 
-# Max time to wait for a euca-delete command to propogate
+# Max time to wait for a euca-delete command to propagate
 export VOLUME_DELETE_TIMEOUT=${SNAPSHOT_DELETE_TIMEOUT:-60}
 
 # The size of the volume we want to boot from; some storage back-ends