make EasyBuild check easyconfig repository

[boegel]

EasyBuild should check the easyconfig repository it dumps easyconfig file to after building, when resolving dependencies for a build or when being run without a supplied easyconfig file.

[akesandgren]

@boegel Since this is basically configurable in the easyconfig file, this could be closed or?

[boegel]

This is about https://github.com/easybuilders/easybuild-framework/pull//1201, so good to close

[boegel]

Note: that change was first included in EasyBuild 2.0