* Avoid useless cat
* Properly quote command line arguments
* Use [ \t] instead of \s for BSD sed
* Do not delete commented out property settings, by matching strictly at start of line
* Add forgotten double-quotes
* Explicitly escape \t (advice by shellcheck.net)
This reverts commit b66e224d79.
if FILE variable contains bash variables (such as $HOME) they are not resolved and script fails (because of 'set -euo pipefail')
Now works on OSX: inline is required since in OSX providing '' as variable does not work.
More reliable OS independent version of this script.
Fixed incorrect backslash count in REGEX variable
Applied recommendations for "if grep" http://mywiki.wooledge.org/BashPitfalls#if_.5Bgrep_foo_myfile.5D