CDL: update the intro text a bit

app.py

@@ -94,8 +94,10 @@ def get_pose_gif(pose:Pose, step:int=1, fps:int=None):
     frames = frames[::step]
     return v.save_gif(None,frames=frames)
 
-
-uploaded_file = st.file_uploader("gimme a .pose file", type=[".pose", ".pose.zst"])
+st.write("# Pose-format explorer")
+st.write("`pose-format` is a toolkit/library for 'handling, manipulation, and visualization of poses'. See [The documentation](https://pose-format.readthedocs.io/en/latest/)"
+st.write("I made this app to help me visualize and understand the format, including different 'components' and 'points', and what they are named.")
+uploaded_file = st.file_uploader("Upload a .pose file", type=[".pose", ".pose.zst"])