Removing Qthreads version 1.9

Version 1.10 of Qthreads seems to be performing as correctly as 1.9 did, so
blowing away the old version.



git-svn-id: http://svn.code.sf.net/p/chapel/code/trunk@21833 3a8e244f-b0f2-452b-bcba-4c88e055c3ca