0.3

Adds letter histogram and query command.

? in place of a guess will show a histogram for letters in remaining
candidate words, with the count being the number of words containing
that letter.

?xyz will show a restricted candidate list and histogram for
remaining words that also contain xyz.

0.2

• Word list path can be configured with a wordListPath argument
• Word length can be configured with a letterCount argument

Platform Independence

Extract code not-essential to CLI

SidleCore now holds structures for representing facts and filtering
abstract word lists. SidleCore provides a sting-based word list with
built-in regular expression support. sidle (the CLI executable) hosts
the previous data-based word list with out-of-process grep filtering.