logic: add name delimiter to NameHierarchy

* NameHierarchy now looks like this: <delimiter>\tm<all the rest>
* made new baseclasses for SettingsMigration and SettingsMigrator
* Use the migration system for SqliteBookmarkStorage as well

bin/app/user/projects/javaparser/javaparser.srctrlprj

@@ -13,7 +13,7 @@
 		\n
 		\tIf you ask yourself where to start, click the symbol linked below.\n
 		\n
-		[com\ts\tp\tngithub\ts\tp\tnjavaparser\ts\tp\tnast\ts\tp\tnbody\ts\tp\tnClassOrInterfaceDeclaration\ts\tp] // <- start here!\n\n
+		[.\tmcom\ts\tp\tngithub\ts\tp\tnjavaparser\ts\tp\tnast\ts\tp\tnbody\ts\tp\tnClassOrInterfaceDeclaration\ts\tp] // <- start here!\n\n
 	</description>
     <source_groups>
         <source_group_7a9e75fc-2cad-42d5-8c5b-c86d02f7b4e4>

bin/app/user/projects/tutorial/tutorial.srctrlprj

@@ -13,7 +13,7 @@
 		LET'S GET STARTED!\n
 		\tTo keep things simple just click the "main" symbol below to start the tour.\n
 		\n
-		[main\tsint\tp()](); // <- start here\n\n
+		[::\tmmain\tsint\tp()](); // <- start here\n\n
 	</description>
     <source_groups>
         <source_group_75041cb3-37c8-45c6-bb8a-1b8b79040f59>