Support for HAProxy 1.8.1 about rpm-haproxy

[khdevel]

@pietervogelaar I also need such RPM, so I have worked on it and here is my PR: #8

Please checkout if it works for you. My build is for Centos7 and it seems to work fine.
I did not check it with special configuration because I have to migrate from 1.5, so it needs a time and tests. But the main process with default configuration works good.

Remark:
When I set an option -W or put master-worker in configuration haproxy.service was in failed state after the systemctl stop haproxy.service was performed. So, it needs to be checked what is the reason of that and fix it.

[DBezemer]

@beeva-carlosleon master-worker probably requires to run haproxy without a pid file, I'll do some testing and if this is the case will release an updated service file together with the 1.8.5 release

[DBezemer]

Finalized in 6602959

[khdevel]

Thank you!

[next-carlosleon]

Remark:
When I set an option -W or put master-worker in configuration haproxy.service was in failed state after the systemctl stop haproxy.service was performed. So, it needs to be checked what is the reason of that and fix it.

I am having the same issue. Do you know what is going on?

Thanks

[next-carlosleon]

Thanks @DBezemer and great work! :)