Modify some spelling mistakes

There are some comment errors, it's modify 'Captial' to 'Capital' in
keystone file, and modify 'possition' to 'position' in openrc file, and
modify 'comming' to 'coming' in stack file, and
modify 'prefered' to 'preferred' in stackrc file.

Change-Id: I0fdd539cbfff842a4ba7fca9100b881443300f9a
diff --git a/lib/keystone b/lib/keystone
index 1061081..749e219 100644
--- a/lib/keystone
+++ b/lib/keystone
@@ -350,7 +350,7 @@
     # The Member role is used by Horizon and Swift so we need to keep it:
     local member_role="member"
 
-    # Captial Member role is legacy hard coded in Horizon / Swift
+    # Capital Member role is legacy hard coded in Horizon / Swift
     # configs. Keep it around.
     get_or_create_role "Member"
 
diff --git a/openrc b/openrc
index 23c173c..37724c5 100644
--- a/openrc
+++ b/openrc
@@ -84,7 +84,7 @@
 # We currently recommend using the version 3 *identity api*.
 #
 
-# If you don't have a working .stackenv, this is the backup possition
+# If you don't have a working .stackenv, this is the backup position
 KEYSTONE_BACKUP=$SERVICE_PROTOCOL://$SERVICE_HOST:5000
 KEYSTONE_AUTH_URI=${KEYSTONE_AUTH_URI:-$KEYSTONE_BACKUP}
 
diff --git a/stack.sh b/stack.sh
index 015ee6e..e924182 100755
--- a/stack.sh
+++ b/stack.sh
@@ -30,7 +30,7 @@
 # NOTE(sdague): why do we explicitly set locale when running stack.sh?
 #
 # Devstack is written in bash, and many functions used throughout
-# devstack process text comming off a command (like the ip command)
+# devstack process text coming off a command (like the ip command)
 # and do transforms using grep, sed, cut, awk on the strings that are
 # returned. Many of these programs are interationalized, which is
 # great for end users, but means that the strings that devstack
diff --git a/stackrc b/stackrc
index 877da82..b03426f 100644
--- a/stackrc
+++ b/stackrc
@@ -80,7 +80,7 @@
 # CELLSV2_SETUP - how we should configure services with cells v2
 #
 # - superconductor - this is one conductor for the api services, and
-#   one per cell managing the compute services. This is prefered
+#   one per cell managing the compute services. This is preferred
 # - singleconductor - this is one conductor for the whole deployment,
 #   this is not recommended, and will be removed in the future.
 CELLSV2_SETUP=${CELLSV2_SETUP:-"superconductor"}
@@ -117,7 +117,7 @@
 # Whether or not to enable Kernel Samepage Merging (KSM) if available.
 # This allows programs that mark their memory as mergeable to share
 # memory pages if they are identical. This is particularly useful with
-# libvirt backends. This reduces memory useage at the cost of CPU overhead
+# libvirt backends. This reduces memory usage at the cost of CPU overhead
 # to scan memory. We default to enabling it because we tend to be more
 # memory constrained than CPU bound.
 ENABLE_KSM=$(trueorfalse True ENABLE_KSM)