fixes issue 863 + set dr_api_exit to true when dr_exit_process() called on app stack
fixes issue 863
+ set dr_api_exit to true when dr_exit_process() called on app stack

git-svn-id: ed337ca7cdb08c0ba29d8fe58632bb7686892c2d@1524 49cc7528-f6fd-11dd-9d1a-b59b2e1864b6

rnk/dynamorio,rnk/dynamorio,rnk/dynamorio,rnk/dynamorio,rnk/dynamorio