[model zoo] download from gist grooming

- invoke by shell
- default download dir to models/
- save to flat dir of owner-gist instead of nested owner/gist

scripts/download_model_from_gist.sh

@@ -1,16 +1,24 @@
-echo "usage: download_model_from_gist.sh <gist_id> <dirname>"
+#!/usr/bin/env sh
 
 GIST=$1
-DIRNAME=$2
+DIRNAME=${2:-./models}
 
-if [ -d "$DIRNAME/$GIST" ]; then
-    echo "$DIRNAME/$GIST already exists! Please make sure you're not overwriting anything important!"
+if [ -z $GIST ]; then
+  echo "usage: download_model_from_gist.sh <gist_id> <dirname>"
+  exit
+fi
+
+GIST_DIR=$(echo $GIST | tr '/' '-')
+MODEL_DIR="$DIRNAME/$GIST_DIR"
+
+if [ -d $MODEL_DIR ]; then
+    echo "$MODEL_DIR already exists! Please make sure you're not overwriting anything important!"
     exit
 fi
 
-echo "Downloading Caffe model info to $DIRNAME/$GIST ..."
-mkdir -p $DIRNAME/$GIST
-wget https://gist.github.com/$GIST/download -O $DIRNAME/$GIST/gist.tar.gz
-tar xzf $DIRNAME/$GIST/gist.tar.gz --directory=$DIRNAME/$GIST --strip-components=1
-rm $DIRNAME/$GIST/gist.tar.gz
+echo "Downloading Caffe model info to $MODEL_DIR ..."
+mkdir -p $MODEL_DIR
+wget https://gist.github.com/$GIST/download -O $MODEL_DIR/gist.tar.gz
+tar xzf $MODEL_DIR/gist.tar.gz --directory=$MODEL_DIR --strip-components=1
+rm $MODEL_DIR/gist.tar.gz
 echo "Done"