install.py script patch

modify about installation guide

README.md

@@ -31,7 +31,8 @@
 1. cd custom_nodes
 1. git clone https://github.com/ltdrdata/ComfyUI-Impact-Pack.git
 3. cd ComfyUI-Impact-Pack
-4. python install.py
+4. (optional) python install.py
+   * Impact Pack will automatically install its dependencies during its initial launch.
 5. Restart ComfyUI
 
 * You can use this colab notebook [colab notebook](https://colab.research.google.com/github/ltdrdata/ComfyUI-Impact-Pack/blob/Main/notebook/comfyui_colab_impact_pack.ipynb) to launch it. This notebook automatically downloads the impact pack to the custom_nodes directory, installs the tested dependencies, and runs it.

install.py

@@ -6,6 +6,7 @@ import subprocess
 comfy_path = '../..'
 
 sys.path.insert(0, os.path.join(os.path.dirname(os.path.realpath(__file__)), "comfy"))
+sys.path.append('.')   # for portable version
 sys.path.append(comfy_path)
 
 
@@ -35,6 +36,7 @@ def remove_olds():
 
 def ensure_pip_packages():
     try:
+        import cv2
         import segment_anything
         from skimage.measure import label, regionprops
         import onnxruntime