Refactor: extract base strategy into separate class
Continue extract strategy refactor...

Clean up context class (WordSquares)
Pend two tests of now private methods.
Continue strategy refactor...

Base strategy class continues all-green on specs
New pivot_word_squares startegy class added (but no tests for that yet)
Ignore tags file.
Add delete_row() to Square class
Add complete? method to Squares
Add to_s() method to Square class
Add exception in Square if row < 1
Extract base strategy refactor complete...

Running with base strategy passes all specs
Remove dependence on external @start_time
Add TODO to improve default represenation & to_s & inspect methods
Adjust spec to ensure no 'leftover' results = OK
DRY: Update spec to handle both strategies in a single loop
Fix bug in clear_on_pivot: didn't clear completely
PivotWordSquares broken...

Re-implementing from scratch to resolve.
Primitive loop working
Modify one_word_square CLI to match new format for strategy
Refactor strategy driver...

Extract method checked_strategy() to handle different strategy inputs/types
Accept strings or recognized classes or set default if nil.
Rewrite PivotWordSquares implementation
Added Noah Clark's word list (shorter than mine)
Remove unused code