Support installation via brew blocked because of incompatibility

[debo]

Alongside @madumlao (I still want to give him credits for the amazing work he did), I worked in the past on phpenv and we also went to a long length to recover access and control of the project as he mentioned here.

Recently I found myself in need to reinstall the tool and I honestly got tired of need to clone the repo and so I started creating brew formulas for both php-build and phpenv. Unfortunately the former cannot be completed/created because, for some strange reason we still have rbenv* executable in the binary folder and I am not sure why those are currently needed.

They were originally introduced with this PR and subsequently update to normal symlink to the phpenv* executables with this one but I really don't see why we would need those at all. Are you happy for me to remove those via a PR and then proceed with adding brew support? What do you people think?