Add lexer test program

Reads file and uses lexer on each line.
Fix some lexer issues

Separate all graphic non-alpha/numeric characters from beginning and
end of words.
Store whether there was whitespace after each word, so toString looks better.
Make word spliting use the same handling for .!? as sentence spliting.

Added test for acronym.
Make 'make clean' remove test object files
Fix crash in lexer
Sort of handle IRC recv errors / disconnect