use Popen instead of getstatusoutput to check for libedit....
use Popen instead of getstatusoutput to check for libedit.
getstatusoutput uses os.popen, and is vulnerable to EINTR weirdness
in environments such as gdb or PyQt.
Exponential falloff is also used, to prevent waiting forever or firing requests too fast, though I haven't had it fire more than once
after moving to Popen.
closes gh-473