minor bugfix
Merge branch 'master' of ssh://github.com/CGATOxford/cgat

Conflicts:
	CGATPipelines/pipeline_docs/pipeline_intervals/trackers/IntervalReport.py
Bug fix for using GSNAP with individual single-end files.
Minor bugfix to GSNAP mapper
CGATPipelines/PipelineUtilities.py: bugfix for attaching multiple databases and add method "write_DataFrame" for inserting pandas dataframes to sql databases.
gtf2table.py: add option "--use-barcodes" for counting unique reads (UMI). Only currently tested with SCRB-seq data.
_gtf2table.pyx: accompanying changes for "--use-barcodes"
add files to enable pull...
Merge branch 'master' of ssh://github.com/CGATOxford/cgat