release global vm lock while waiting for curl_perform to finish.
store headers.
move magic constants to #defines.
move non-ruby C code out into it's own files.
add file for multi.
start stubbing out multi api.
move logic to instance methods (initialize and run).  convience methods just create a new instance and invoke run.
Merge pull request #1 from ledbettj/unblock

Not quite ready for master, but needs some of the changes in multi.
move straight ruby code back out into ruby.
move response out of C into ruby.
pull options out of opts hash when constructing request.
move more request logic out into ruby.
remove unused SELF parameter.
add accessors, sort things alphabetically in case of OCD.
Merge pull request #2 from ledbettj/rb-ize

Ruby-ize code that doesn't need to be in C.
actually start working on the multi code again.
major refactor looking towards implementing curl_multi functionality.
pull curl handle setopts out of run.
first stab at actual multi implementation (currently still holds vm lock)
spec cleanups.