Add Predis timeout

[antriver]

trafficstars

This adds the ability to set an expiration time on the lock when using the Predis Redis driver.

It follows the procedure recommended in the Redis docs here: https://redis.io/commands/setnx

[antriver]

Hi @arvenil

Thanks for this package.

I see you've made some significant changes in master. If there is any chance of this PR getting merged I will update it to reflect those changes. Could you let me know if it's worth me spending the time on that?

Currently I have merged master into my branch but due to the changes it's broken and should not be merged.

Thanks, Anthony

[deminy]

Few months ago I merged this PR manually ( you can see it from https://github.com/deminy/ninja-mutex ) and used it in some production environment for data migration (for tens of millions of records at least). Everything worked fine so I'd recommend to accept this PR. Thanks

[antriver]

Hi @arvenil and @deminy I've remade this PR based on the latest master, and without the destructor/exception changes. Would you mind giving it another look?

[arvenil]

@antriver I'm ok with anything that doesn't brake tests, but travis test run is broken right now 🤷