[libcalamares] Tidy some bits

- Explain what the library is for (briefly) in the CMakeLists
 - Settings should use the right export macro

src/libcalamares/CMakeLists.txt

@@ -1,3 +1,6 @@
+# libcalamares is the non-GUI part of Calamares, which includes handling
+# translations, configurations, logging, utilities, global storage, and (non-GUI) jobs.
+
 add_definitions(
     ${QT_DEFINITIONS}
     -DQT_SHARED

src/libcalamares/Settings.cpp

@@ -21,7 +21,6 @@
 
 #include "Settings.h"
 
-// #include "utils/CalamaresUtils.h"
 #include "utils/Dirs.h"
 #include "utils/Logger.h"
 #include "utils/Yaml.h"

src/libcalamares/Settings.h

@@ -22,7 +22,7 @@
 #ifndef SETTINGS_H
 #define SETTINGS_H
 
-#include "UiDllMacro.h"
+#include "DllMacro.h"
 #include "Typedefs.h"
 
 #include <QObject>
@@ -32,7 +32,7 @@
 namespace Calamares
 {
 
-class UIDLLEXPORT Settings : public QObject
+class DLLEXPORT Settings : public QObject
 {
     Q_OBJECT
 public: