revert #89 as that version of curl does work on some systems

i propose we revert this change by @eXsio - jackalope-jackrabbit works fine on my ubuntu 14.04 with `lib-curl[7.35.0]`. but composer is refusing to install...

instead, we should find somewhere in the doc (faq?) where we can mention the error and say upgrading curl might fix it.

revert #95