Adding support for the shake sensor

[FMounz]

Description:

This PR adds the support for the shake sensor. The user can now call the function cpx.shake() and see the effects,

Type of change

Please delete options that are not relevant.

• New feature (non-breaking change which adds functionality)

Limitations:

Please describe limitations of this PR

Testing:

• Add to code.py an example code that use cpx.shake(). The Simulator should be updated accordingly. Example:

from adafruit_circuitplayground.express import cpx
while True:
    cpx.red_led = cpx.shake()

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• Any dependent changes have been merged and published in downstream modules

[DIGarnier]

Little review :)

[LukeSlev]

@FMounz Some comments, something funky is goin on

[LukeSlev]

Can we add a different onFocus? hard to tell I clicked on the button @FMounz

Michelle insisted on having this one maybe talk to her

[LukeSlev]

Also cause this is a new feature and we have tests on the python side already would you be cool to add tests for this?

[LukeSlev]

Blocked until we get @MichelleYAOOO gives feedback

[jonathanwangg]

Looks good, pending some changes.

[jonathanwangg]

LGTM.