Implemented SessionManager and TextChannelService + several improvements and fixes

src/storage/keyring.ts

@@ -1,6 +1,6 @@
 export interface KeyringAPI {
     set(key: string, value: any): void;
     get(key: string): string;
+    getAll(): string[];
     delete(key: string): void;
-    flush(): void;
 }

src/storage/keyvalue.ts

@@ -0,0 +1,6 @@
+export interface KeyValueAPI {
+    set(key: string, value: any): void;
+    get(key: string): string;
+    delete(key: string): void;
+    flush(): void;
+}