Fix indent

This commit removes below interpreter warning.

* warning: mismatched indentations at 'end' with 'case'
Fix to redefine reader method

This commit removes below interpreter warning.

* warning: method redefined
Declare an ivar via #initialize

This commit removes below interpreter warning.

* warning: instance variable @{ivar} not initialized
Merge pull request #173 from kachick/improve-remove_warnings

Remove some interpreter warnings