Ensure that the deploy script is also covered by Travis runs

[jmichelp]

Expected Behavior

The deploy.py script should be covered by Travis CI to catch errors.

This will imply several things:

• add a --dry-run parameter to the script to run all the actions except execution of JLinkExe
• split compilation and flash operations (also useful to support more flashing methods such as USB bootloader, OpenOCD, etc.)
• assess if tockloader also has such a dry-run flag
• modify Travis configuration to run deploy script with the different parameters

Actual Behavior

Script is not run.

Steps to Reproduce the Problem

N/A

Specifications

• Version: N/A
• Platform: N/A

[jmichelp]

As suggested during the review of PR #49, we should also:

• Add linter for python and markdown
• Check for proper formatting of python and markdown files

[gendx]

The workflows/boards_build.yml already tests ./deploy.py --board=<board> --no-app --programmer=none. I guess the --programmer=none corresponds to the --dry-run parameter proposed in this issue.

Should we add anything else? I'd say at the very least not only testing --no-app.

[kaczmarczyck]

Several --programmer=none are added.