made perl's Time::HiRes a strong requirement, resolves #739

.tmux.conf

@@ -1675,6 +1675,9 @@ run 'cut -c3- "$TMUX_CONF" | sh -s _apply_configuration'
 #     if ! command -v perl > /dev/null 2>&1; then
 #       tmux run -b 'tmux set display-time 3000 \; display "This configuration requires perl" \; set -u display-time \; run "sleep 3" \; kill-server'
 #       return
+#       if ! perl -MTime::HiRes -e1 > /dev/null 2>&1; then
+#         tmux run -b 'tmux set display-time 3000 \; display "This configuration requires perl Time::HiRes" \; set -u display-time \; run "sleep 3" \; kill-server'
+#       fi
 #     fi
 #     if ! command -v sed > /dev/null 2>&1; then
 #       tmux run -b 'tmux set display-time 3000 \; display "This configuration requires sed" \; set -u display-time \; run "sleep 3" \; kill-server'

README.md

@@ -11,7 +11,7 @@ Installation
 Requirements:
 
   - tmux **`>= 2.6`** running inside Linux, Mac, OpenBSD, Cygwin or WSL
-  - awk, perl and sed
+  - awk, perl (with Time::HiRes support) and sed
   - outside of tmux, `$TERM` must be set to `xterm-256color`
 
 ⚠️ Before installing, you may want to backup your existing configuration.