What's what in here?

eta	Interpreter for ETA program.
eas	The Eta ASsembler, which compiles EAS code into "real" ETA.
easy	Wrapper for eas and eta: compile and run an EAS program.
etaword	Tool to find whole words incorporating significant sequences.
etainst	Tool to find significant sequences within words/phrases.

Also, "pip.eta" and "hello.eta" -- the first two cosmetically complete
ETA programs ever written -- live here for now.  They really belong in
"../pit" but that would be too dangerous -- "make clean" or even a
"easy {pip,hello}" would destroy them.
