Validate the expansion count.
Add workflow name to error message.
Merge branch 'validate_expansion_count' into merge_all

Conflicts:
	nipype/pipeline/utils.py
Revert "Validate the expansion count."

This reverts commit ce1996c1604512974497efb085cc93f27a8557ad.

Conflicts:

	nipype/pipeline/utils.py
Merge branch 'validate_expansion_count' into merge_all

Conflicts:
	nipype/pipeline/utils.py
Merge branch 'merge_all'

Conflicts:
	nipype/pipeline/utils.py