style: reformat C/C++ sources and headers with clang-format

Run clang-format over all project C/C++ source and header files
(.c, .cpp, .cc, .h, .hpp, .hh, .m, .mm) under app/ and tests/.
Non-source files (svg, qm, qrc, etc.) were not touched.

tests/gtest/plugin_support_test.cpp

@@ -4,7 +4,5 @@
 
 TEST(PluginSupport, LoadPluginsEmptyPath)
 {
-	EXPECT_NO_THROW({
-		olive::plugin::loadPlugins(QString());
-	});
+	EXPECT_NO_THROW({ olive::plugin::loadPlugins(QString()); });
 }