refactor(scripts): Structure code as per codestyle

Fix #1636
Refactor code according to code style
Constants, Functions, Script

scripts/openvpn/clientStat.sh

@@ -3,11 +3,6 @@
 
 STATUS_LOG="/var/log/openvpn-status.log"
 
-if [[ ! -f "${STATUS_LOG}" ]]; then
-  err "The file: ${STATUS_LOG} was not found!"
-  exit 1
-fi
-
 err() {
   echo "[$(date +'%Y-%m-%dT%H:%M:%S%z')]: $*" >&2
 }
@@ -72,6 +67,11 @@ listClients() {
   } | column -t -s $'\t'
 }
 
+if [[ ! -f "${STATUS_LOG}" ]]; then
+  err "The file: ${STATUS_LOG} was not found!"
+  exit 1
+fi
+
 if [[ "$#" -eq 0 ]]; then
   HR=1
   listClients