improved the way add_gapfill.r handles years; the added function in add_gapfill.r made add_gapfill_singleyear.r obsolete and it was deleted from ohi_clean_fxns.r. Also, new system creates rows by year for Southern Islands rgn_ids and Antarctica (rgn_id=213)
this will be overwritten
committing this, hoping to be able to merge then

Merge branch 'master' of https://github.com/jules32/ohiprep

Conflicts:
	Global/WEF-Economics_v2014/data_prep.R