Add MarsBased

[davidgg]

This is a modified version of the Contributing Guidelines.

This pull request adheres to the repository's Code of Conduct.

• I am an employee of the company mentioned and confirm all included details are correct
• This PR contains housekeeping only (URL edits, copy changes etc)
• You know your alphabet - company is listed in alphabetical order in the README
• The company directly hires employees. No bootcamps / freelance sites / etc
• The company added hires remote employees, or positions are available to remote workers and are clearly illustrated as such
• A company profile is included - Required for new additions. (This can be a basic outline but at least something please)
• Any missing parts from the profile, please use <Unknown> to allow for future completion
• Remote status has details regarding how the culture includes remote employees, how the company integrated remote workers, etc
• Region details any restrictions to applicants based on geography
• How to apply details the best approach for new applications, page on site where open position are listed, and any other help available for job hunters

This closes #403

[auto-nylen]

Hi @davidgg, thanks for your contribution!

Our automated checks detected some problems with your pull request (as of commit 863f95d). See below for details:

README.md: Company is listed out of order: "Marketade" (should be before "MarsBased")

1 problem detected

Please fix these issues and push a new commit to this pull request.

[auto-nylen]

Hi @davidgg, thanks for updating the pull request! According to our automated checks, everything looks OK now (as of commit e201601). ✔️

[nylen]

Gràcies!