grep, sed and tr work differently on MacOS

[daghan]

The current setup script doesn't work on MacOS (Catalina) without the changes to grep, sed and tr

for tr, replace this:
dbpass=$(dd if=/dev/urandom bs=128 count=1 2>/dev/null| tr -dc _A-Z-a-z-0-9)
with this (add LC_CTYPE):
dbpass=$(dd if=/dev/urandom bs=128 count=1 2>/dev/null| LC_CTYPE=C tr -dc _A-Z-a-z-0-9)

jq -r '.SolutionStacks[]' | egrep '.+Amazon Linux.+Docker.+' | head -1)"
jq -r '.SolutionStacks[]' | grep -P '.+Amazon Linux.+Docker.+' | head -1)"
with this (use egrep vs. grep -P):
jq -r '.SolutionStacks[]' | egrep '.+Amazon Linux.+Docker.+' | head -1)"

for sed, replace this:
sed -i "s/POSTGRESHOSTREPLACEME/$dbhost/" tmp/$identifier/ebs-options.json || fail
with this (-i option requires a file extension, ex: ".bak"):
sed -i ".bak" "s/POSTGRESHOSTREPLACEME/$dbhost/" tmp/$identifier/ebs-options.json || fail