Add a script to write tags

[queengooborg]

This PR primarily adds a script to write RFID tags. In addition, some other script cleanups are performed:

• Move common functions to lib/init.py
• Update parse.py to accept JSON dumps
• Fix imports
• Ignore Python cache files
• Use run_command() in traceKeyExtractor
• No need to explicitly exit pm3 prompt
• Print paths in run_command
• Add a script to write tags