doc update

.github/workflows/DocCleanup.yml

+name: Doc Preview Cleanup
+
+on:
+  pull_request:
+    types: [closed]
+
+jobs:
+  doc-preview-cleanup:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout gh-pages branch
+        uses: actions/checkout@v2
+        with:
+          ref: gh-pages
+
+      - name: Delete preview and history
+        run: |
+            git config user.name "Documenter.jl"
+            git config user.email "documenter@juliadocs.github.io"
+            git rm -rf "previews/PR$PRNUM"
+            git commit -m "delete preview"
+            git branch gh-pages-new $(echo "delete history" | git commit-tree HEAD^{tree})
+        env:
+            PRNUM: ${{ github.event.number }}
+
+      - name: Push changes
+        run: |
+            git push --force origin gh-pages-new:gh-pages
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docs/Project.toml

+[deps]
+Documenter = "e30172f5-a6a5-5a46-863b-614d45cd2de4"
+
+[compat]
+Documenter = "0.26"
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docs/make.jl

 using Documenter, CobraTools
-cd("docs")
+
 
 makedocs(
     sitename="CobraTools.jl",
@@ -13,6 +13,8 @@ makedocs(
         "Equilibrator Interface" => "thermo_tools.md",
         "Brenda Interface" => "brenda_tools.jl"
     ]
-    )
+)
 
-cd("..")
\ No newline at end of file
+deploydocs(
+    repo = "github.com/stelmo/CobraTools.jl.git",
+)
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