A few updates, cleanup updated weather module.

modules/convert/convert.sh

@@ -1,12 +1,17 @@
+#!/usr/bin/env bash
 [ -f functions.sh ] && source functions.sh
 
-units="$(command -v units)"
+# Dependencies required by this module
+dependencies=("units")
 
 shift
 chan="$1"
 shift
-if [ -z "$units" ]; then
-msg "$chan" "I do not have access to units."
-else
-msg "$chan" "$($units -v ${*#* } | head -n1 | tr -d '[:space:]')"
+
+# Check dependencies before running
+if ! check_dependencies "${dependencies[@]}"; then
+    msg "$chan" "$1: This module requires: ${dependencies[*]}"
+    exit 1
 fi
+
+msg "$chan" "$(units -v ${*#* } | head -n1 | tr -d '[:space:]')"