change so that strings use an 'in' test instead of being compiled into regex
change so that strings use an 'in' test instead of being compiled into regex

cypreess/csvkit,metasoarous/csvkit,jpalvarezf/csvkit,kyeoh/csvkit,bradparks/csvkit__query_join_filter_CSV_cli,KarrieK/csvkit,bmispelon/csvkit,arowla/csvkit,unpingco/csvkit,doganmeh/csvkit,haginara/csvkit,nriyer/csvkit,Tabea-K/csvkit,tlevine/csvkit,snuggles08/csvkit,barentsen/csvkit,matterker/csvkit,wjr1985/csvkit,dannguyen/csvkit,archaeogeek/csvkit,reubano/csvkit,gepuro/csvkit,Jobava/csvkit,elcritch/csvkit,aequitas/csvkit,themiurgo/csvkit,onyxfish/csvkit,moradology/csvkit,wireservice/csvkit