Update readme links and references

README.md

@@ -44,12 +44,12 @@ You will need the following to build BHoM:
 
 ## Want to contribute? ##
 
-BHoM is an open-source project and would be nothing without its community. Take a look at our contributing guidelines and tips [here](https://github.com/BHoM/BHoM/blob/master/CONTRIBUTING.md).
+BHoM is an open-source project and would be nothing without its community. Take a look at our contributing guidelines and tips [here](https://github.com/BHoM/BHoM/blob/main/CONTRIBUTING.md).
 
 
 ## Licence ##
 
 BHoM is free software licenced under GNU Lesser General Public Licence - [https://www.gnu.org/licenses/lgpl-3.0.html](https://www.gnu.org/licenses/lgpl-3.0.html)  
 Each contributor holds copyright over their respective contributions.
 The project versioning (Git) records all such contribution source information.
-See [LICENSE](https://github.com/BHoM/BHoM/blob/master/LICENSE) and [COPYRIGHT_HEADER](https://github.com/BHoM/BHoM/blob/master/COPYRIGHT_HEADER.txt).
+See [LICENSE](https://github.com/BHoM/BHoM/blob/main/LICENSE) and [COPYRIGHT_HEADER](https://github.com/BHoM/BHoM/blob/main/COPYRIGHT_HEADER.txt).