CLJS-2234: Make build scripts optionally less verbose

Author: darwin

script/aot_core

@@ -1,6 +1,10 @@
 #!/usr/bin/env bash
 
-set -ex
+set -e
+
+if [[ -z "$CLJS_SCRIPT_QUIET" ]]; then
+  set -x
+fi
 
 FILE_SEP='/'
 PATH_SEP=':'

script/build

@@ -3,7 +3,11 @@
 # This script must be run within the ClojureScript top-level project
 # directory.
 
-set -ex
+set -e
+
+if [[ -z "$CLJS_SCRIPT_QUIET" ]]; then
+  set -x
+fi
 
 cd `dirname $0`/..
 rm -rf target

script/uberjar

@@ -3,7 +3,11 @@
 # This script must be run within the ClojureScript top-level project
 # directory.
 
-set -ex
+set -e
+
+if [[ -z "$CLJS_SCRIPT_QUIET" ]]; then
+  set -x
+fi
 
 # The command `git describe --match v0.0` will return a string like
 #