typo fixes for root level scripts
typo fixes for regen scripts
typo fix for vms script
typo fixes for win32 scripts
typo fix for util script
typo fix for os2 module
making DOS stand out in dosify
typo fixes for porting pod
note optimiser change to optimizer to be consistent with other uses of optimizer in todo
typo fixes for porting modules
typo fixes for porting scripts
typo fixes for version pod
typo fixes for Unicode module
typo fix for File::Find
typo fixes for Benchmark
typo fix for _charnames
typo fix for DB
typo fix for Thread
typo fix for perl5db
typo fixes for B modules
uses of optimise change to optimize to be consistent with other uses of optimize
typo  fixes for Math::BigInt