Adds a userPrefs.h file, default blank, used for default settings for custom builds (#4325)

* add a userPrefs.h file, default blank, which can be used to easily set defaults on custom builds.

* Add Splash Screen to userPrefs

* Add channel 0 defaults to userPrefs.h

* CONFIG_LORA_IGNORE_MQTT_DEFAULT

* Unify naming for USERPREFS defines

---------

Co-authored-by: Ben Meadors <benmmeadors@gmail.com>

src/graphics/Screen.cpp

@@ -20,6 +20,7 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
 */
 #include "Screen.h"
+#include "../userPrefs.h"
 #include "configuration.h"
 #if HAS_SCREEN
 #include <OLEDDisplay.h>
@@ -156,7 +157,11 @@ static void drawIconScreen(const char *upperMsg, OLEDDisplay *display, OLEDDispl
 
     display->setFont(FONT_MEDIUM);
     display->setTextAlignment(TEXT_ALIGN_LEFT);
+#ifdef SPLASH_TITLE_USERPREFS
+    const char *title = SPLASH_TITLE_USERPREFS;
+#else
     const char *title = "meshtastic.org";
+#endif
     display->drawString(x + getStringCenteredX(title), y + SCREEN_HEIGHT - FONT_HEIGHT_MEDIUM, title);
     display->setFont(FONT_SMALL);