more pruning & code refactoring (#1011)

* improve error handling to show more details

* improve the way it checks for root password

* consistant getty_override

* streamline verbose mode

* remove v4 scripts

* small tweaks

ct/nginxproxymanager-v5.sh

@@ -33,20 +33,14 @@ BFR="\\r\\033[K"
 HOLD="-"
 CM="${GN}✓${CL}"
 CROSS="${RD}✗${CL}"
-set -o errexit
-set -o errtrace
-set -o nounset
-set -o pipefail
-shopt -s expand_aliases
-alias die='EXIT=$? LINE=$LINENO error_exit'
-trap die ERR
-function error_exit() {
-  trap - ERR
-  local reason="Unknown failure occurred."
-  local msg="${1:-$reason}"
-  local flag="${RD}‼ ERROR ${CL}$EXIT@$LINE"
-  echo -e "$flag $msg" 1>&2
-  exit $EXIT
+set -Eeuo pipefail
+trap 'error_handler $LINENO "$BASH_COMMAND"' ERR
+function error_handler() {
+  local exit_code="$?"
+  local line_number="$1"
+  local command="$2"
+  local error_message="${RD}[ERROR]${CL} in line ${RD}$line_number${CL}: exit code ${RD}$exit_code${CL}: while executing command ${YW}$command${CL}"
+  echo -e "\n$error_message\n"
 }
 
 function msg_info() {
@@ -143,7 +137,6 @@ function default_settings() {
   SSH="no"
   echo -e "${DGN}Enable Verbose Mode: ${BGN}No${CL}"
   VERB="no"
-  VERB2="silent"
   echo -e "${BL}Creating a ${APP} LXC using the above default settings${CL}"
 }
 function advanced_settings() {
@@ -318,7 +311,6 @@ function advanced_settings() {
   else
       echo -e "${DGN}Enable Verbose Mode: ${BGN}No${CL}"
       VERB="no"
-      VERB2="silent"
   fi
   if (whiptail --title "ADVANCED SETTINGS COMPLETE" --yesno "Ready to create ${APP} LXC?" --no-button Do-Over 10 58); then
     echo -e "${RD}Creating a ${APP} LXC using the above advanced settings${CL}"
@@ -472,7 +464,6 @@ TEMP_DIR=$(mktemp -d)
 pushd $TEMP_DIR >/dev/null
 export DISABLEIPV6=$DISABLEIP6
 export VERBOSE=$VERB
-export STD=$VERB2
 export SSH_ROOT=${SSH}
 export CTID=$CT_ID
 export PCT_OSTYPE=$var_os