docs: Update Releases.md to note v1.7.0 release

Signed-off-by: Kevin O'Connor <[email protected]>

docs: Update Releases.md to note v1.6.0 release

Signed-off-by: Kevin O'Connor <[email protected]>

docs: Update Releases.md to note v1.5.0 release

Signed-off-by: Kevin O'Connor <[email protected]>

docs: Update Releases.md to note v1.4.1 release

Signed-off-by: Kevin O'Connor <[email protected]>

can2040: Set TXPENDING during pio_sm_setup()

Signed-off-by: Kevin O'Connor <[email protected]>

docs: Note that can2040 doesn't dynamically allocate memory in API.md

Signed-off-by: Kevin O'Connor <[email protected]>

README: Update rp2040 url and use "CAN bus" instead of "CANbus"

Signed-off-by: Kevin O'Connor <[email protected]>

can2040: Initial commit of "software canbus" implementation

Signed-off-by: Kevin O'Connor <[email protected]>