Add notice to readme warning of active development (#267)

* Added a simple note to the top of the readme indicating active development
* Moved Important comment to a visually less weird location

README.md

@@ -1,12 +1,18 @@
 # CFA Scenarios Model
+
 [Overview](#overview) |
 [Model Structure](#model-structure) |
 [Quick Start](#quick-start) |
 [Data Sources](#data-sources) |
 [Project Admins](#project-admins) |
 [Fine Text and Disclaimers](#general-disclaimer)
+
 ## Overview
 
+> [!IMPORTANT]
+> This repository is under active development and will be substantially refactored in the near future.
+> Please look around, but we advise against working with this code until it has stabilized.
+
 This repository is for the design and implementation of a Scenarios forecasting model, built by the Scenarios team within CFA-Predict.
 
 Currently, we aim to use this code to forecast different disease tranmission scenarios with a compartmental mechanistic ODE model.  This model is under development with transmission of SARS-CoV-2 as our primary focus.  We plan to apply this model to the transmission of other respiratory viruses such as influenza and RSV.  We aim to provide enough flexibility for the code users to explore a variety of scenarios, but also making certain design decisions that allow for fast computation and fitting as well as code readability.