removed should syntax and replaced with expect to follow RSPEC convention
removed old code
 updated hard_find_mode spec to replace should syntax
median_spec update
refactored letter_grade_spec
updated comma_spec
refactored pad_spec, changed 'doesnt pad a long array' not sure if right
finished week 4 rspec refactor
finished pad array spec
fixed RPN calc spec
fixed 1_die_spec
fixed 2_die_spec
fixed 3_die_spec
fixed 6_validate_credit_card
Merge pull request #13 from Devbootcamp/rspec_update

Rspec update
updated challenge instructions
removed second "I"
removed second "I" for clarity
translated driver code to test
ready to go