TurtleDownloader

[BramComyn]

Feature description

• emit event dataSize from request to notify download method of new download size
• make it so that the buffer is held within the download function
• remove unnecessary getters, setters and class members

Goal

Make it so that the download method can be called multiple times in a row, without having to wait for the last call to resolve. This will simplify the code.

[BramComyn]

Only have to fix the tests now