Unify instance_{rebuild,provision}.html

This commit unifies the templates for rebuild and provision as they are
nearly identical.

internal/dis/component/server/admin/html/instance_system.html

@@ -0,0 +1,50 @@
+{{ $rebuild := .Rebuild }}
+<div class="pure-u-1-1">
+    <form class="pure-form pure-form-aligned" id="system">
+        <fieldset>
+            <legend>Main Parameters</legend>
+
+            <div class="pure-control-group">
+                <label for="slug">Slug</label>
+                <input name="slug" id="slug" placeholder="" {{ if $rebuild }} readonly="readonly" value="{{ .Slug }}" {{ end }}>
+            </div>
+        </fieldset>
+        <fieldset>
+            <legend>System Parameters</legend>
+
+            <div class="pure-control-group">
+                <label for="php">PHP Version</label>
+                <select id="php">
+                    {{ $PHP := .System.PHP }}
+                    <option {{ if $rebuild }}{{ if eq $PHP "" }}selected{{ end }}{{ else }}selected{{ end }}>Default ({{ .DefaultPHPVersion }})</option>
+                    {{ range .PHPVersions }}
+                    <option {{ if $rebuild }}{{ if eq $PHP . }}selected{{ end }}{{ end }} value="{{ . }}">{{ . }}</option>
+                    {{ end }}
+                </select>
+            </div>
+            <label for="opcacheDevelopment" class="pure-checkbox">
+                <input {{ if $rebuild }}{{ if .System.OpCacheDevelopment }}checked{{end}}{{end}} type="checkbox" id="opcacheDevelopment" />
+                Opache Development Configuration
+            </label>
+            <div class="pure-control-group" class="pure-input-1">
+                <label for="contentsecuritypolicy">Content Security Policy</label>
+                <input name="contentsecuritypolicy" id="contentsecuritypolicy" list="content-security-policy" {{ if $rebuild }}value="{{ .System.ContentSecurityPolicy }}" {{ end }}>
+            </div>
+        </fieldset>
+        <fieldset>
+            <legend>Profile</legend>
+
+            <div class="pure-control-group">
+                Not yet available
+            </div>
+        </fieldset>
+
+        <input type="submit" value="{{ if $rebuild }}Rebuild{{ else }}Provision{{ end }}" class="pure-button">
+    </form>
+</div>
+
+<datalist id="content-security-policy">
+    {{ range .ContentSecurityPolicies }}
+    <option value="{{ . }}">
+        {{ end }}
+</datalist>