support microbadger labels

[jstrachan]

these look handy:
https://microbadger.com/#/labels

[rhuss]

How can a support look like ? From http://label-schema.org/ we could extract certain immutable build type labels and try to extract them automatically. This could be switched on with a specific configuration option.

The current discussion about those labels can be found here.

AFAIS these labels could be extracted directly from build information in the pom.xml:

• build-date
• name
• description
• url
• vcs-url
• vcs-ref
• vendor
• version

From the <run> section we could extract:

• docker.cmd