token-cli: Add directions for building and running tests (#3673)

Author: joncinque

token/cli/README.md

@@ -1,3 +1,35 @@
 # SPL Token program command-line utility
 
 A basic command-line for creating and using SPL Tokens.  See https://spl.solana.com/token for more details
+
+## Build
+
+To build the CLI locally, simply run:
+
+```sh
+cargo build
+```
+
+## Testing
+
+The tests require locally built programs for Token, Token-2022, and Associated
+Token Account. To build these, you can run:
+
+```sh
+BUILD_DEPENDENT_PROGRAMS=1 cargo build
+```
+
+This method uses the local `build.rs` file, which can be error-prone, so alternatively,
+you can build the programs by running the following commands from this directory:
+
+```sh
+cargo build-sbf --manifest-path ../program/Cargo.toml
+cargo build-sbf --manifest-path ../program-2022/Cargo.toml
+cargo build-sbf --manifest-path ../../associated-token-account/program/Cargo.toml
+```
+
+After that, you can run the tests as any other Rust project:
+
+```sh
+cargo test
+```