Improved build status image (Added optional params for shield.io)

[corpsee]

Contribution Type: new feature|cosmetic Link to Intent to Implement: Link to Bug:

This pull request affects the following areas:

• [X] Front-End
• [ ] Builder
• [ ] Build Plugins

In raising this pull request, I confirm the following (please check boxes):

• [X] I have read and understood the contributing guidelines?
• [X] I have checked that another pull request for this purpose does not exist.
• [X] I have considered, and confirmed that this submission will be valuable to others.
• [X] I have created or updated the relevant documentation for this change on the PHPCI Wiki.
• [X] Do the PHPCI tests pass?

Detailed description of change: Improved build status image (Added optional params for shield.io)