Changes for version 0.22
- added a notice about 4096 read limits on some machines noticed by Ed Morandi.
- built an rpm .spec file with the help of cpan2rpm.
- adding TESTPORT=... as a Makefile.PL option to not step on MakeMaker's feet.
- making "modemtest" an installable script (which adds #! to top).
- cleaning up "modemtest" args and output.
- reversing configure report so "best" case reports "yes" for all.
- handling ancient libcs with odd POSIX.pm _SC_CLK_TCK behavior with diagnostic help from David Dyck
- added test case explicitly for get_tick_count
- Device::SerialPort - Linux/POSIX emulation of Win32::SerialPort functions.