minor, check for curl
fix, PEBKAC, check for R >= 2.0.0
minor, transparently download remote files via libcurl
fix, PEBKAC, avoid resource leak upon ute_open
fix, PEBKAC, initialise tmp file name on stack upon every call of ute_open()
minor, use custom writer instead of curl's to avoid problems with O_EXCL
minor, unlink the actual temp file
fix, PEBKAC, clear our memory with our clearing routine
minor, use yuck's mktempp()
minor, use mexErrMsgTxt() only when followed by return
Merge branch 'core/mex-iter'

* core/mex-iter:
  minor, use mexErrMsgTxt() only when followed by return
  minor, use yuck's mktempp()
  fix, PEBKAC, clear our memory with our clearing routine
  minor, unlink the actual temp file
  minor, use custom writer instead of curl's to avoid problems with O_EXCL
  fix, PEBKAC, initialise tmp file name on stack upon every call of ute_open()
  fix, PEBKAC, avoid resource leak upon ute_open
  minor, transparently download remote files via libcurl
  fix, PEBKAC, check for R >= 2.0.0
  minor, check for curl
minor, safe-guard against malicious input
minor, support ute_open()ing of multiple files (via cell array)
minor, for symmetry support ute_close()ing of multiple handles (via cell array)
Merge branch 'core/mex-iter'

* core/mex-iter:
  minor, for symmetry support ute_close()ing of multiple handles (via cell array)
  minor, support ute_open()ing of multiple files (via cell array)
  minor, safe-guard against malicious input