added database driven system configurations with admin screen (#647)

src/Configuration/TimesheetConfiguration.php

@@ -0,0 +1,45 @@
+<?php
+
+/*
+ * This file is part of the Kimai time-tracking app.
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace App\Configuration;
+
+class TimesheetConfiguration implements SystemBundleConfiguration
+{
+    use StringAccessibleConfigTrait;
+
+    public function getPrefix(): string
+    {
+        return 'timesheet';
+    }
+
+    public function isAllowFutureTimes(): bool
+    {
+        return (bool) $this->find('rules.allow_future_times');
+    }
+
+    public function isDurationOnly(): bool
+    {
+        return (bool) $this->find('duration_only');
+    }
+
+    public function isMarkdownEnabled(): bool
+    {
+        return (bool) $this->find('markdown_content');
+    }
+
+    public function getActiveEntriesHardLimit(): int
+    {
+        return (int) $this->find('active_entries.hard_limit');
+    }
+
+    public function getActiveEntriesSoftLimit(): int
+    {
+        return (int) $this->find('active_entries.soft_limit');
+    }
+}