Add a bash script to run the test-suite.

scripts/test.sh

@@ -0,0 +1,26 @@
+#!/usr/bin/sh
+
+file="/.flatpak-info"
+if [ -f "$file" ]
+then
+    # If you open a build terminal with gnome-builder
+    source /usr/lib/sdk/rust-stable/enable.sh
+    export CARGO_HOME=target/cargo-home/
+fi
+
+export RUSTFLAGS="--cfg rayon_unstable"
+export RUSTBACKTRACE="1"
+
+rustc --version
+cargo --version
+# cargo fmt --version
+
+cargo build --all && \
+cargo test -- --test-threads=1 && \
+cargo test -- --test-threads=1 --ignored
+
+# Rustfmt from the flatpak bundle tends to be outdated,
+# will probably get better when rustfmt stabilizes
+# cargo fmt --all -- --write-mode=diff
+
+# cargo bench large