add edit-method stub: deprecation warning, use edit
Improved Pry::CodeCollector so it accept multiple -i/o ranges

i.e play -i 1..3 -i 5..9 now works
added spec for save-file for multiple -i ranges
updated play_spec.rb to check for errors

Also added play spec for multi-ranged -i options but does not work
for some weird reason?!
added fix-indent command

Re-indents the eval_string, useful for amend_line and play, etc
show-source: prettier error messages
play and amend-line: now use fix-indent to correct broken indentation