add WSH <-> WSE conversion tool (#16)

* Update README.md

* update to new QGIS (and pytest)

* wse_to_wsh

* wse_to_wsh

README.md

@@ -4,19 +4,21 @@
 
 QGIS Processing scripts for rescaling or changing the resolution of flood hazard rasters.
 
+Tested against QGIS 3.34.5
+
 ## UPDATES
 -**2024 01 19**: new *pixel* based isolated filter for the *Resolution Enhancer* tool
 
 
-## Description
+## 01 Description
 Includes the following tools:
 - **Resolution Enhancer (WSE)**: Three methods for interpolating a high resolution WSE grid using a high resolution DEM and simple hydraulic assumptions described in [Bryant et. al., (2022)](https://hess.copernicus.org/preprints/hess-2023-156/). For more advanced applications and features, see the [FloodDownscaler2](https://github.com/cefect/FloodDownscaler2) project.
 - **Aggregation via Averaging**: Two methods for coarsening flood hazard grids described in [Bryant et. al., (2022)](https://doi.org/10.1029/2023WR035100)
 
 
 The algorithms are tested against QGIS 3.28.11 and require [WhiteboxTools for QGIS plugin](https://www.whiteboxgeo.com/manual/wbt_book/qgis_plugin.html).
 
-## 1 Installation Instructions
+## 02 Installation Instructions
 
 ### download the scripts
 download the algorithms of interest from the [processing folder](floodrescaler/processing) to your local machine
@@ -30,14 +32,14 @@ In the QGIS [Processing Toolbox](https://docs.qgis.org/3.22/en/docs/user_manual/
 Ensure the [WhiteboxTools for QGIS plugin](https://www.whiteboxgeo.com/manual/wbt_book/qgis_plugin.html) is installed and configured. 
 Note this is only required for the Downscaling/CostGrow algo.  Tested against v2.2.0.
 
-## 2 Use
+## 03 Use
 Instructions are provided on the algorithm dialog
 
-## 3 Example Data
+## 04 Example Data
 
 Example data is provided in the [examples](/examples) folder
 
-## 4 Attribution
+## 05 Attribution
 
 If you use these tools for your work, please cite the following:
 
@@ -79,7 +81,7 @@ If you use these tools for your work, please cite the following:
 
 ```
 
-## 5 Development
+## 06 Development
 
 - create a virtual environment from the supported QGIS version and the `./requirements.txt` file. 
 - add a ./definitions.py file similar to the below