Merge branch 'bugfix/build-sh-missing-directory' into 'rebase/glitch-soc'

Bugfix: build.sh: use TARGET env variable and check it

See merge request !17

build.sh

 #!/bin/sh
-TARGET="../pleroma" # Where pleroma’s repository is sitting
+TARGET="${TARGET:-../pleroma}" # Where pleroma’s repository is sitting
+
+if [[ ! -d "${TARGET}/priv/static" ]]
+then
+	echo "Error: ${TARGET}/priv/static directory is missing, are you sure TARGET is set to a pleroma repository?"
+	echo "Info: TARGET=${TARGET}"
+	exit 1
+fi
 
 yarn install -D