Update cross-build script to zip up results

.gitignore

@@ -3,3 +3,4 @@
 /.env
 /.idea
 /*.bak
+/*.gz

cross-build.sh

@@ -1,18 +1,29 @@
 #!/usr/bin/env bash
 set -euo pipefail
 
+PACKAGE_VERSION=$(sed -n 's/^version *= *"\(.*\)"/\1/p' "Cargo.toml")
+echo "Cross-building for version ${PACKAGE_VERSION}"
+
+PROFILE=release-lto
+
 echo "Building for Linux (GNU libc)"
+LINUX_FLAVOR=linux-gnu
+TARGET=x86_64-unknown-${LINUX_FLAVOR}
 # rustup target add x86_64-unknown-linux-gnu
-cargo auditable build --profile=release-lto --target=x86_64-unknown-linux-gnu
-ls -lah target/x86_64-unknown-linux-gnu/release-lto/k8sfwd
+cargo auditable build --profile=${PROFILE} --target=${TARGET}
+ls -lah target/${TARGET}/${PROFILE}/k8sfwd
+gzip --keep -c target/${TARGET}/${PROFILE}/k8sfwd > "k8sfwd-${PACKAGE_VERSION}-${LINUX_FLAVOR}.gz"
 
 echo "Building for Linux (musl)"
+LINUX_FLAVOR=linux-musl
+TARGET=x86_64-unknown-${LINUX_FLAVOR}
 # rustup target add x86_64-unknown-linux-musl
-cargo auditable build --profile=release-lto --target=x86_64-unknown-linux-musl
-ls -lah target/x86_64-unknown-linux-musl/release-lto/k8sfwd
+cargo auditable build --profile=${PROFILE} --target=${TARGET}
+ls -lah target/${TARGET}/${PROFILE}/k8sfwd
+gzip --keep -c target/${TARGET}/${PROFILE}/k8sfwd > "k8sfwd-${PACKAGE_VERSION}-${LINUX_FLAVOR}.gz"
 
 # TODO: Add OSX support
 # echo "Building for Apple Darwin"
 # # rustup target add x86_64-apple-darwin
-# cargo auditable build --profile=release-lto --target=x86_64-apple-darwin
-# ls -lah target/x86_64-apple-darwin/release-lto/k8sfwd
+# cargo auditable build --profile=${PROFILE} --target=x86_64-apple-darwin
+# ls -lah target/x86_64-apple-darwin/${PROFILE}/k8sfwd