Merge pull request #1167 from cogentcore/install-docs

document that you should re-install the core tool each time you update to a new version of Cogent Core

docs/content/2-setup/0-install.md

@@ -1,7 +1,7 @@
 Note: we recommend you read the [basics](../basics) and [tutorials](../tutorials) before you start developing with Cogent Core on your system. Complete all of the following steps to install Cogent Core:
 
 1. Download and install Go from [the Go website](https://go.dev/doc/install) if you do not already have Go 1.22+ installed.
-2. Run `go install cogentcore.org/core/cmd/core@main` to install the Cogent Core command line tool.
+2. Run `go install cogentcore.org/core/cmd/core@main` to install the Cogent Core command line tool. You should run this command again each time you update to a new version of Cogent Core.
 3. Run `core setup` to install platform-specific dependencies. Please first read all of the information below:
     * This installs the [xcode-tools](https://mac.install.guide/commandlinetools/4) on macOS, various graphics libraries on Linux, and [w64devkit](https://github.com/skeeto/w64devkit) and [Git](https://git-scm.com/download/win) on Windows.
     * You should run the command from your home directory.