Merge branch 'simple_cargo' into 'master'

cargo: Allow for manual cargo invokations

See merge request Librem5/squeekboard!158

README.md

@@ -62,6 +62,15 @@ $ cd ../build/
 $ src/squeekboard
 ```
 
+### Maintenance
+
+Use the `cargo.sh` script for maintaining the Cargo part of the build. The script takes the usual Cargo commands, after the first 2 positionsl arguments: source directory, and output artifact. So, `cargo test` becomes:
+
+```
+cd build_dir
+/source_path/cargo.sh /source_path '' test
+```
+
 ### Testing
 
 ```

cargo.sh

@@ -1,13 +1,22 @@
-#!/bin/sh
+#!/bin/bash
+
+# This script manages Cargo operations
+# while keeping the artifact directory within the build tree
+# instead of the source tree
+
 set -e
 
+SOURCE_DIR="$1"
+
 export CARGO_TARGET_DIR=`pwd`
 if [ ! -z ${2} ]; then
     OUT_PATH=`realpath "${2}"`
 fi
 
-cd $1
+cd $SOURCE_DIR
-cargo $3 -p rs
+shift
+shift
+cargo $BUILD_ARG $@
 
 if [ ! -z ${OUT_PATH} ]; then
     cp "${CARGO_TARGET_DIR}"/debug/librs.a "${OUT_PATH}"