Compiler support: fix issues with registerService function (#104)

- Throwing error if `registerService` was called on a non-initialized peer.
- Fix issue with incorrect context being passed to class-based implementations of user services
- Fix typo in JSDoc

src/internal/FluencePeer.ts

@@ -109,7 +109,7 @@ export interface PeerConfig {
  */
 export interface PeerStatus {
     /**
-     * Is the peer connected to network or not
+     * Is the peer initialized or not
      */
     isInitialized: Boolean;