[boost] [range] Borland and GCC-2.95 workarounds for iostreams

Hi Thorsten, I made two changes to range, which should only affect gcc-2.95 and Borland: - in begin.hpp and end.hpp I applied some of the Borland workarounds to gcc-2.95 as well - in iterator_range.hpp, I removed some Borland workarounds which were causing iostreams to fail on Borland, and which did not seem to be necessary. The same tests passed with and without the workarounds. Jonathan