util script: trying a new way to reference the lib

this way uses don't have to be sure that /path/to/SmileTrain appears as
a subfolder of their python path
seq_table: added functionality and caller option

currently filenames are fixed
tools: added check_barcodes
tools: added reverse complement barcoding
renamed util/ to tools/
moved user.cfg to a template
Merge pull request #16 from swo/master

added some tools & cleaned up a few technicalities