Fix and TOMLize tools/powerline

Part of #174

recipes/tools/powerline/recipe.sh

@@ -1,2 +0,0 @@
-GIT=https://github.com/jD91mZM2/powerline-rs
-CARGOFLAGS="--no-default-features --features chrono"

recipes/tools/powerline/recipe.toml

@@ -0,0 +1,17 @@
+[source]
+git = "https://github.com/jD91mZM2/powerline-rs"
+
+[build]
+template = "custom"
+script = """
+export CARGOFLAGS="--no-default-features --features chrono"
+
+# --locked uses a reallyyyy old redox_syscall and libc which fails
+${COOKBOOK_CARGO} install \
+    --path "${COOKBOOK_SOURCE}/${PACKAGE_PATH}" \
+    --root "${COOKBOOK_STAGE}/usr" \
+    --no-track \
+    --no-default-features \
+    --features chrono \
+    ${install_flags}
+"""