Remove privateMain description from readme

README.md

@@ -20,9 +20,3 @@ To see the default values of each property please view `MMCommon.props`
 *TODO*
 
 Most users should clone the `micro-manager` repository and use this repo as a submodule.
-
-### Branches (for maintainers only)
-This repository consists of two primary branches: `main` and `privateMain`.  
-Changes made to the `main` branch are merged into `privateMain`. The only difference between the two branches is that `privateMain` includes a private repository as a submodule containing device adapter code which is not permitted to be made publicly available.  
-Note: Please do not modify public files in the `privateMain` branch. Changes made in `main` should be merged into `privateMain` but never the other way around.  
-Note: After checking out the `privateMain` branch it may be necessary to run the following command to make sure that all submodules are up to date in your local copy: `git submodule update --init --recursive`.