Rename file, add update in else and fix bug with ! -d not being present

tangerineui.sh

@@ -1,5 +1,5 @@
 #!/usr/bin/env bash
-# This script installs the Tangerine UI theme.
+# This script installs/updates the Tangerine UI theme.
 # Author - packetcat
 
 # Tangerine UI repository directory
@@ -8,9 +8,13 @@ REPO="$HOME/TangerineUI-for-Mastodon"
 INSTALLDIR="$HOME/live"
 
 # Clone Tangerine UI repository if it doesn't exist
+# If repo exists, just pull updates.
 
-if [ -d "$REPO" ]; then
+if [ ! -d "$REPO" ]; then
   git clone https://github.com/nileane/TangerineUI-for-Mastodon.git $REPO
+else
+  cd $REPO
+  git pull
 fi
 
 # Copy Tangerine UI files into your Mastodon install's styles directory