A lot of changes

Remove unused constructor of messages::Message
Fixed LimitedQueueSnapshot _-prefixes
Changed LimitedQueueSnapshot's usage of int to std::size_t
ColorScheme is no longer a singleton
Created a "BaseWidget" class which is pretty much a QWidget except it
has a reference of ColorScheme since most widgets will need a reference
to the style they should use.
BaseWidget can be implemented either with a BaseWidget parent (which
will copy the ColorScheme reference from the parent) or with a
normal QWidget parent and an explicit ColorScheme reference.
Save main window geometry on close
Fix font changing in the Settings Dialog
Update settings library version

src/application.hpp

@@ -1,8 +1,10 @@
 #pragma once
 
 #include "channelmanager.hpp"
+#include "colorscheme.hpp"
 #include "emotemanager.hpp"
 #include "ircmanager.hpp"
+#include "messagefactory.hpp"
 #include "resources.hpp"
 #include "windowmanager.hpp"
 
@@ -19,10 +21,12 @@ public:
     int run(QApplication &qtApp);
 
     WindowManager windowManager;
+    ColorScheme colorScheme;
     EmoteManager emoteManager;
     Resources resources;
     ChannelManager channelManager;
     IrcManager ircManager;
+    MessageFactory messageFactory;
 };
 
 }  // namespace chatterino