added link in metapackage readme and liblsl readme to JOSS submission

Author: zeyus

README.md

@@ -9,6 +9,7 @@ This is the meta repo for the dart native liblsl package.
 Packages:
 
 - [liblsl](./packages/liblsl): The main package for liblsl. [![Pub Publisher](https://img.shields.io/pub/publisher/liblsl?style=flat-square)](https://pub.dev/publishers/zeyus.com/packages) [![Pub Version](https://img.shields.io/pub/v/liblsl)](https://pub.dev/packages/liblsl)
+  - [JOSS paper](./packages/liblsl/paper/paper.md): markdown version of the JOSS paper (pending review).
 - [liblsl_test](./packages/liblsl_test): An integration test so you can try out liblsl with flutter on any supported target platform.
 - [liblsl_timing](./packages/liblsl_timing): App based multi-device latency, sync and interactive timing tests with automatic device coordination via LSL
 - [liblsl_analysis](./packages/liblsl_analysis): Analysis of results from the timing tests in [liblsl_timing](./packages/liblsl_timing)

packages/liblsl/README.md

@@ -4,6 +4,7 @@
 
 This package provides a Dart wrapper for liblsl, using the dart native-assets build system and ffi.
 
+Submitted [JOSS paper](./paper/paper.md): markdown version of the JOSS paper (pending review).
 
 ## Targets