Add GitHub CI for deployment and corresponding scripts

Set up GitHub Action CI to deploy page. Currently using the new GitHub
feature to directly publish an artifact as a deployment instead of
needing to go through a separate gh-pages branch. This makes sense for
this repository because everything is generated by the vimhelp tool
anyway and we never need to directly commit anything to a branch. By
using an artifact based approach we won't have to worry about the Git
repository getting too big (e.g. Neovim actually has a manual history
pruning step to prune their gh-pages branch for this reason).

Added some scripts to manually parse MacVim's version info from the
source files so we can display that in the main page.

Currently, the CI is going to run every night, which is not ideal. We
should find a way to cache the last version we generated, and do not
re-regenerate it unless this repo itself has changed, or MacVim has been
updated.

Author: ychin

.github/FUNDING.yml

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+github: macvim-dev
+open_collective: macvim

.github/dependabot.yml

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+version: 2
+updates:
+  - package-ecosystem: "github-actions"
+    directory: "/"
+    schedule:
+      interval: "weekly"

.github/workflows/ci.yaml

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+name: MacVim Documentation Build
+
+on:
+  push:
+    branches:
+      - 'main'
+  schedule:
+    - cron: "50 3 * * *" # 3:50 am UTC every day. Just a random time intentionally picked to be not during busy hours.
+  workflow_dispatch:
+
+# Allow one concurrent deployment
+concurrency:
+  group: "pages"
+  cancel-in-progress: true
+
+env:
+  MACVIM_REPO: 'macvim-dev/macvim'
+  MACVIM_DIR: ${{ format('{0}/macvim', github.workspace) }}
+
+jobs:
+  # Build the page and upload it as an artifact
+  build:
+    runs-on: ubuntu-latest
+    permissions:
+      contents: read
+    steps:
+      - uses: actions/checkout@v3
+
+      - name: Checkout MacVim
+        uses: actions/checkout@v3
+        with:
+          repository: ${{ env.MACVIM_REPO }}
+          path: 'macvim'
+
+      - uses: actions/setup-python@v4
+        with:
+          python-version: '3.x'
+          cache: 'pip'
+          cache-dependency-path: 'vimhelp/requirements.txt'
+
+      - name: Set up vimhelp
+        run: |
+          pip install -r vimhelp/requirements.txt
+
+      - name: Set up commit / version environmental vars
+        run: |
+          cd "$MACVIM_DIR"
+          printf 'MACVIM_COMMIT=%s\n' $(git rev-parse HEAD) >> $GITHUB_ENV
+          printf 'MACVIM_VERSION=%s\n' $(${GITHUB_WORKSPACE}/scripts/extract_macvim_version ./src) >> $GITHUB_ENV
+          printf 'VIM_VERSION=%s\n' $(${GITHUB_WORKSPACE}/scripts/extract_vim_version ./src) >> $GITHUB_ENV
+
+      - name: Build the documentation
+        run: |
+          echo "MacVim commit: ${MACVIM_COMMIT}"
+          echo "MacVim release: ${MACVIM_VERSION}"
+          echo "Vim version: ${VIM_VERSION}"
+
+          version_string="r${MACVIM_VERSION} (Vim ${VIM_VERSION})"
+          echo "Version string: $version_string"
+
+          cd vimhelp
+          python3 scripts/h2h.py -i "$MACVIM_DIR/runtime/doc" -o ../build --project macvim --web-version --version "$version_string" --commit "$MACVIM_COMMIT"
+
+      - name: Upload page artifact
+        uses: actions/upload-pages-artifact@v1
+        with:
+          path: build
+
+  # Deploy the artifact to the page
+  deploy:
+    needs: build
+
+    permissions:
+      pages: write      # to deploy to Pages
+      id-token: write   # to verify the deployment originates from an appropriate source
+
+    environment:
+      name: github-pages
+      url: ${{ steps.deployment.outputs.page_url }}
+
+    runs-on: ubuntu-latest
+    steps:
+      - name: Deploy to GitHub Pages
+        id: deployment
+        uses: actions/deploy-pages@v1

scripts/extract_macvim_version

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+#!/bin/bash
+
+set -e -o pipefail
+
+srcdir=$1
+
+macvim_release_number=`grep -A1 CFBundleVersion $srcdir/MacVim/Info.plist|tail -1|sed -E -e 's/^.*<string>([[:digit:]]+).*/\1/'`
+
+echo "$macvim_release_number"

scripts/extract_vim_version

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+#!/bin/bash
+
+set -e -o pipefail
+
+srcdir=$1
+
+# Logic was extracted from MacVim's configure.ac
+vim_major_version_string=`grep -m 1 'define.*VIM_VERSION_MAJOR' $srcdir/version.h|sed -E -e 's/^.*([[:digit:]]+).*/\1/'`
+vim_minor_version_string=`/usr/bin/grep -m 1 'define.*VIM_VERSION_MINOR' $srcdir/version.h|sed -E -e 's/^.*([[:digit:]]+).*/\1/'`
+snapshot=`/usr/bin/grep -C2 "Add new patch number below this line" $srcdir/version.c|tail -1|sed -E -e 's/^ *([[:digit:]]+),.*/\1/'`
+
+vim_short_version_string="$vim_major_version_string.$vim_minor_version_string.$snapshot"
+
+echo "$vim_short_version_string"