Revert "Merge remote-tracking branch 'origin/xrootd-move-to-3.3.3' into IB/CMSSW_7_0_X/devel-gcc48"

This reverts commit 054aaecf7a6289b775d611f301c1f043ea6d7c43, reversing
changes made to f0718c0ea140b81e03dd49bd18d80e301b3c0376.
Merge pull request #184 from davidlt/revert-xrootd-move-to-3.3.3

[CMSSW_7_0_X][48] Revert xrootd 3.3.3