Bulk convert control files. (#19986)

```
function Convert-Control {
    Param($full)
    .\vcpkg.exe format-manifest $full
    $root = $full.Substring(0, $full.Length - 7) # CONTROL
    $new = $root + 'vcpkg.json'
    $content = Get-Content -Raw $new
    $asJson = ConvertFrom-Json $content -AsHashtable -Depth 100
    $oldVersion = $asJson['port-version']
    if ($null -eq $oldVersion) {
        $oldVersionFull = $asJson['version-string']
        Write-Host "Got version $oldVersionFull"
        $match = [System.Text.RegularExpressions.Regex]::Match($oldVersionFull, '^(.+)-(\d+)$')
        if ($match.Success -and -not [System.Text.RegularExpressions.Regex]::IsMatch($oldVersionFull, '^\d\d\d\d-\d\d-\d\d$')) {
            $newFullVersion = [string]$match.Groups[1].Value
            $oldVersion = [int]$match.Groups[2].Value
            Write-Host "newFullVersion $newFullVersion oldVersion $oldVersion"
            $newVersion = $oldVersion + 1
            $asJson['version-string'] = $newFullVersion
            Write-Host "Previous version for $full extracted from version field -- setting version-string $newFullVersion and port-version $newVersion"
        } else {
            Write-Host "No previous version for $full -- setting 1"
            $newVersion = 1
        }
    } else {
        $newVersion = [int]$oldVersion + 1
        Write-Host "New version for $full : $newVersion"
    }

    $asJson['port-version'] = $newVersion

    $content = ConvertTo-Json $asJson -Depth 100
    Set-Content -Path $new -Value $content
    .\vcpkg.exe format-manifest $new
}

Get-ChildItem ports\CONTROL -Recurse | Foreach-Object {
    Convert-Control $_.FullName
}

git commit -am "this message"
.\vcpkg.exe x-add-version -all
git commit -a --amend
```

2 files changed, 14 insertions, 7 deletions

diff --git a/ports/crashpad/CONTROL b/ports/crashpad/CONTROL
deleted file mode 100644
index dab2671f6..000000000
--- a/ports/crashpad/CONTROL
+++ /dev/null
@@ -1,7 +0,0 @@
-Source: crashpad
-Version: 2020-03-18
-Homepage: https://chromium.googlesource.com/crashpad/crashpad/+/master/README.md
-Description: Crashpad is a crash-reporting system.
-  Crashpad is a library for capturing, storing and transmitting postmortem crash reports from a client to an upstream collection server. Crashpad aims to make it possible for clients to capture process state at the time of crash with the best possible fidelity and coverage, with the minimum of fuss.
-Build-Depends: zlib
-Supports: x64 & (osx|windows)
diff --git a/ports/crashpad/vcpkg.json b/ports/crashpad/vcpkg.json
new file mode 100644
index 000000000..a47031499
--- /dev/null
+++ b/ports/crashpad/vcpkg.json
@@ -0,0 +1,14 @@
+{
+  "name": "crashpad",
+  "version-string": "2020-03-18",
+  "port-version": 1,
+  "description": [
+    "Crashpad is a crash-reporting system.",
+    "Crashpad is a library for capturing, storing and transmitting postmortem crash reports from a client to an upstream collection server. Crashpad aims to make it possible for clients to capture process state at the time of crash with the best possible fidelity and coverage, with the minimum of fuss."
+  ],
+  "homepage": "https://chromium.googlesource.com/crashpad/crashpad/+/master/README.md",
+  "supports": "x64 & (osx | windows)",
+  "dependencies": [
+    "zlib"
+  ]
+}