MSVC 6.0.

ENH: Merging changes from KWSys-IOS-bp to KWSys-IOS-b2t-1-mp to main tree.  This corresponds to the same merge in KWSys.  Fixes for bootstrapping on cygwin are also included.

ENH: Merging changes from KWSys-IOS-bp to KWSys-IOS-b2t-1-mp to main tree.  This introduces separate kwsys_ios and kwsys_stl macros needed to support all platforms.

ENH: Even better. Only replace when path longer than 20 characters. Also replace parent directory. That way it will replace for related projects.

ENH: Added SetPipeShared method to allow stdout and stderr pipes to be shared with the parent process.

ERR: Ok, think before commit... This fixes two build problems. The missing brace and the std::string signature is different on gcc 2.95 and gcc 3.3.