v1.3.0

Correction of behavioral differences with Bash

We fixed some differences of output between bash and sush. Followings are major revisions.

• Omitted evaluation of substring expansion for undefined variables
• Behavior of read
  • implemented -t (timeout) option
  • Fixed some rules toward spaces or escaped spaces

See https://github.com/shellgei/rusty_bash_test/blob/v1.3.0/test_fixed.bash for details on the specific corrections.

Full Changelog: v1.2.9...v1.3.0