Fix conditional blocks and some typo errors

[laggardkernel]

• Conditional blocks in careful_rm.alias.sh has been optimized.
• Some typo errors have been fixed in the Second pass
• Final check has been merged into Second pass. Cause Final check is only for those failed Second pass and redundant for those passed Second pass.
• Python version check has been fixed as what is told in README.md: Python > 2.6, not Python >= 2.6