DEF_OPT_AS_INT isn't actually used anywhere, remove it for now.
Create a standalone program that outputs the wtperf documentation in
doxygen format, then compile & call it as part of running dist/s_docs.
Reference #1147.
Move CONFIG_OPT enum/structure into config_opt.h, move doxygen DEF_OPT
same structures/configuration as wtperf.  Reference #1147.
Remove extra reference to bulk-load page.  Rename tune_bulk_load for
consistency.