Creation of NVDA development roadmap (nvaccess#17117)

Summary of the issue:
NV Access is pleased to share our NVDA development roadmap, outlining our short, medium, and long-term priorities for NVDA. Our goals in sharing this roadmap are to foster greater transparency and collaboration with our community.
* Alignment: To align community development efforts with NV Access's priorities for a healthy and vibrant NVDA and add-on developer ecosystem.
* Excitement: To generate enthusiasm and anticipation for upcoming features and improvements.
* Transparency: To openly share our development focus and direction.
* Dialogue: To encourage discussion and feedback between the developer community and NV Access.

Description of user facing changes:
Updated `readme.md` to link to the roadmap on the NV Access website.

readme.md

@@ -8,6 +8,7 @@ Please note: the NVDA project has a [Citizen and Contributor Code of Conduct](CO
 
 The NVDA project is guided by a [product vision statement and set of principles](./projectDocs/product_vision.md).
 The vision and principles should be always considered when planning features and prioritizing work.
+NV Access also maintains a [development roadmap](https://www.nvaccess.org/post/nvda-roadmap/) of NVDA features and supporting infrastructure work.
 
 NVDA is available under a modified GNU General Public License version 2.
 Please refer to [our license](./copying.txt) for more information.