[lsd-cat]

Add support to connect to ADB over serial port.
Adds pySerial as a dependency.

Usage is as simple as

device.ConnectDevice(port_path=None, serial="/dev/ttyS11,115200")

In the case the baudrate is not specified, default is 115200.
tty is the keyword that triggers the SerialHandler instead of the Usb or Tcp ones.

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[JeffLIrion]

You're welcome to submit a pull request to the adb-shell repo. If you'd like to do so, please follow the existing docentation style (numpydoc style), add tests for this serial transport, and create a subclass of AdbDevice. You can follow the example of the TCP transport:

• tcp_transport.py
• AdbDeviceTcp class
• test_tcp_transport.py