Custom optional custom file.

[luison]

Hi. I can't say I love bash but I've modified the script to support the optional load of a file nginx-custom.options that can include any of both of your NGINX_MODULES and NGINX_OPTIONS variables.

This allows to personalise the standard compile modules (was my case) without loosing the possibility to update your script or having to modify it again as I've add it to the git ignore list. Left a "sample" one.

Feel free to include it if you find it of interest.

I've had to redo it as I've noticed you've, just today, modified considerably the code. Is done in any case although I'll admit I liked better your previous "echo" style and log interface.

By the way I only found this today which is not updated but might be of interest to you too: https://github.com/naologic/nginx-builder