Add snap packaging (#93)

* snapcraft init

* update packaging

* update packaging

* update packaging

* update packaging

* update packaging

* update packaging

* snap worked

* fix locale warning

* polish code

* update metainfo

* update icon

* update icon

* update message

3rdparty/qt-unix-signals/sigwatch.h

@@ -0,0 +1,59 @@
+/*
+ * Unix signal watcher for Qt.
+ *
+ * Copyright (C) 2014 Simon Knopp
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+#ifndef SIGWATCH_H
+#define SIGWATCH_H
+
+#include <QObject>
+#include <signal.h>
+
+class UnixSignalWatcherPrivate;
+
+
+/*!
+ * \brief The UnixSignalWatcher class converts Unix signals to Qt signals.
+ *
+ * To watch for a given signal, e.g. \c SIGINT, call \c watchForSignal(SIGINT)
+ * and \c connect() your handler to unixSignal().
+ */
+
+class UnixSignalWatcher : public QObject
+{
+    Q_OBJECT
+public:
+    explicit UnixSignalWatcher(QObject *parent = 0);
+    ~UnixSignalWatcher();
+
+    void watchForSignal(int signal);
+
+signals:
+    void unixSignal(int signal);
+
+private:
+    UnixSignalWatcherPrivate * const d_ptr;
+    Q_DECLARE_PRIVATE(UnixSignalWatcher)
+    Q_PRIVATE_SLOT(d_func(), void _q_onNotify(int))
+};
+
+#endif // SIGWATCH_H