Speed up Atom package installation script

atom.symlink/install.sh

@@ -21,14 +21,18 @@ if test "$(which apm)"; then
     wakatime
   "
   for module in $modules; do
-    apm list | grep -q "$module" || apm install "$module"
+    if [[ ! -d "$HOME/.atom/packages/$module" ]]; then
+      apm install "$module"
+    fi
   done
 
   modules="
     metrics
     exception-reporting
   "
   for module in $modules; do
-    apm list | grep -q "$module" || apm remove "$module"
+    if [[ -d "$HOME/.atom/packages/$module" ]]; then
+      apm remove "$module"
+    fi
   done
 fi