Add isConnected method

Adds method to see if there is an active Bluetooth connection

Code Optimization

This release is focused on optimizing the codebase to further follow Kotlin design, courtesy of @aouerfelli.

Bluetooth Communication

This release has support for Bluetooth communication via IO stream read and write in bytes.

• scanning for new devices
• pairing a new device
• data transfer between Bluetooth devices
• BLE support

Initial release

What's working

• enable/disable Bluetooth
• viewing all paired devices
• finding paired devices
• connecting to a paired device
• ending a Bluetooth connection

Upcoming in future releases

• scanning for new devices
• pairing a new device
• data transfer between Bluetooth devices
• BLE support