Refined exceptions thrown and caught for interpret
Merge remote-tracking branch 'origin/master' into khyean
Merge remote-tracking branch 'origin/khyean'
Update README.txt
Unit Test module added
Revert "Unit Test module added"

This reverts commit a10acbea488f5ab5a3504567db990648b2671aee.
Unit Test Module added
Update README.txt
slight changes to new format of commands , in readme
Interpreter updated to accept new cmd formats

new formats are for search / edit / delete / display
logging got deleted accidentally while i was reverting previously,
restoring it now
Merge remote-tracking branch 'origin/master' into Qingtao_Add/Delete/Undo