Update README.md

It does not work on php versions before 5.3.0 at all.
Removing what appears to be old information from the README, to make it more obvious what you need, or in this case, don't need to do
Allows hiding entire modpacks from the API
Quick fix to update MD5s for resources. Edit your pack and save (no changes)  to force MD5 update.
Updated / to redirect to dashboard instead.
Merge branch 'master' of https://github.com/bloodarowman/TechnicSolder