Add some basic error-checking

contrib/fresh_clone_compile_and_run.sh

@@ -4,13 +4,15 @@
 # file COPYING or https://www.gnu.org/licenses/gpl-3.0.en.html
 
 # Usage: $0 BRANCH JOBS
+# TODO: default to master branch with 2 jobs
+
+set -eu -o pipefail
 
 BRANCH=$1
 
 git clone https://git.hush.is/hush/hush3
 cd hush3
 git checkout $BRANCH
-# Build with 2 cores
 # You need 2GB of RAM per core, don't use too many
 # (GB of RAM)/2 - 1 is the optimal core count for compiling Hush
 # `nproc` tells you how many cores you have