android.md: Update
chromium.py: Add repo_type and init
aosp.py: Add revert() and change repo_ver to repo_date
aosp.py: Fix the logic to check connection and file name in flash image
util.py: Add more global variables and handle symbolic better in copy_file()
test-daily.py: Check return value for command execution
chromium.py: Change clean() to revert()
.zshrc: Ensure the creation of symbolic link
chromium.py: Use internal function to install packages
chromium.py: Change install() to internal function