Implemented LaunchId and FileSelection, updated Notes (#281)

- Implemented `LaunchId` to keep track of the apps that are started
- Implemented `FileSelection` app to select existing and/or new files.
- Moved some re-usable file functionality to `tt::file::`
- Renamed `Files` app to `FileBrowser`
- Updated `Notes` app to use new `FileSelection` functionality, and cleaned it up a bit.
- General code cleanliness improvements

Tactility/Source/Tactility.cpp

@@ -37,7 +37,8 @@ namespace app {
     namespace chat { extern const AppManifest manifest; }
     namespace boot { extern const AppManifest manifest; }
     namespace display { extern const AppManifest manifest; }
-    namespace files { extern const AppManifest manifest; }
+    namespace filebrowser { extern const AppManifest manifest; }
+    namespace fileselection { extern const AppManifest manifest; }
     namespace gpio { extern const AppManifest manifest; }
     namespace gpssettings { extern const AppManifest manifest; }
     namespace i2cscanner { extern const AppManifest manifest; }
@@ -78,7 +79,8 @@ static void registerSystemApps() {
     addApp(app::applist::manifest);
     addApp(app::calculator::manifest);
     addApp(app::display::manifest);
-    addApp(app::files::manifest);
+    addApp(app::filebrowser::manifest);
+    addApp(app::fileselection::manifest);
     addApp(app::gpio::manifest);
     addApp(app::gpssettings::manifest);
     addApp(app::i2cscanner::manifest);