Update readme and workflow for LFS

Author: JimBobSquarePants

.github/workflows/build-and-test.yml

@@ -56,6 +56,20 @@ jobs:
 
         steps:
             - uses: actions/checkout@v2
+            
+            # See https://github.com/actions/checkout/issues/165#issuecomment-657673315
+            - name: Create LFS file list
+              run: git lfs ls-files -l | cut -d' ' -f1 | sort > .lfs-assets-id
+
+            - name: Restore LFS cache
+              uses: actions/cache@v2
+              id: lfs-cache
+              with:
+                path: .git/lfs
+                key: ${{ runner.os }}-lfs-${{ hashFiles('.lfs-assets-id') }}-v1
+
+            - name: Git LFS Pull
+              run: git lfs pull
 
             - name: Install NuGet
               uses: NuGet/setup-nuget@v1

README.md

@@ -76,7 +76,9 @@ If working with Windows please ensure that you have enabled long file paths in g
 git config --system core.longpaths true
 ```
 
-This repository contains [git submodules](https://blog.github.com/2016-02-01-working-with-submodules/). To add the submodules to the project, navigate to the repository root and type:
+This repository uses [Git Large File Storage](https://docs.github.com/en/github/managing-large-files/installing-git-large-file-storage). Please follow the linked instructions to ensure you have it set up in your environment.
+
+This repository contains [Git Submodules](https://blog.github.com/2016-02-01-working-with-submodules/). To add the submodules to the project, navigate to the repository root and type:
 
 ``` bash
 git submodule update --init --recursive