[libcalamares] Take ownership of the versioning headers

- The sources were in src/calamares but processed and generated
  in libcalamares, which is weird at best.
- Generate an "extended" version header.
- Use the extended version in the logger and nowhere else.
- While here, minor coding style cleanups

The overall change here means that after running CMake, only
Logger.cpp needs to be rebuilt (if the extended version has
changed) and not a handful of other files that don't need the
full version number, but do happen to include CalamaresVersion.h

src/libcalamares/CMakeLists.txt

@@ -27,8 +27,10 @@ include_directories( ${CMAKE_CURRENT_BINARY_DIR} ${CMAKE_CURRENT_SOURCE_DIR} )
 
 configure_file( ${CMAKE_CURRENT_SOURCE_DIR}/CalamaresConfig.h.in
                 ${CMAKE_CURRENT_BINARY_DIR}/CalamaresConfig.h )
-configure_file( ${CMAKE_CURRENT_SOURCE_DIR}/../calamares/CalamaresVersion.h.in
+configure_file( ${CMAKE_CURRENT_SOURCE_DIR}/CalamaresVersion.h.in
                 ${CMAKE_CURRENT_BINARY_DIR}/CalamaresVersion.h )
+configure_file( ${CMAKE_CURRENT_SOURCE_DIR}/CalamaresVersionX.h.in
+                ${CMAKE_CURRENT_BINARY_DIR}/CalamaresVersionX.h )
 
 set( OPTIONAL_PRIVATE_LIBRARIES "" )
 set( OPTIONAL_PUBLIC_LIBRARIES "" )

src/libcalamares/utils/Logger.cpp

@@ -3,6 +3,7 @@
  *   SPDX-FileCopyrightText: 2010-2011 Christian Muehlhaeuser <muesli@tomahawk-player.org>
  *   SPDX-FileCopyrightText: 2014 Teo Mrnjavac <teo@kde.org>
  *   SPDX-FileCopyrightText: 2017 Adriaan de Groot <groot@kde.org>
+ *   SPDX-License-Identifier: GPL-3.0-or-later
  *
  *
  *   Calamares is free software: you can redistribute it and/or modify
@@ -18,15 +19,12 @@
  *   You should have received a copy of the GNU General Public License
  *   along with Calamares. If not, see <http://www.gnu.org/licenses/>.
  *
- *   SPDX-License-Identifier: GPL-3.0-or-later
- *   License-Filename: LICENSE
- *
  */
 
 #include "Logger.h"
 
-#include <fstream>
-#include <iostream>
+#include "CalamaresVersionX.h"
+#include "utils/Dirs.h"
 
 #include <QCoreApplication>
 #include <QDir>
@@ -35,10 +33,10 @@
 #include <QTime>
 #include <QVariant>
 
-#include "CalamaresVersion.h"
-#include "utils/Dirs.h"
+#include <fstream>
+#include <iostream>
 
-#define LOGFILE_SIZE 1024 * 256
+static constexpr const int LOGFILE_SIZE = 1024 * 256;
 
 static std::ofstream logfile;
 static unsigned int s_threshold =