qiime/emperor — pull request #98 by ElDeveloper (2013-06-04 05:15:56+00:00)
Title: Order is preserved when concatenating headers

preprocess_mapping_file now preserves the order when column
concatenation is specified. If the columns Treatment and DOB are
intended to be concatenated, different results will be generated if the
user specifies 'DOB&&Treatment' and 'Treatment&&DOB'.

Fixes #93