Restrict scraper names to alpha, underscore and dash
Restrict scraper names to alpha, underscore and dash

This is so that GitHub doesn't end up doing any translation of the name
(for instance '/' gets changed to '-') and the names match up between
GitHub and Morph. Fixes #184

otherchirps/morph,otherchirps/morph,OpenAddressesUK/morph,openaustralia/morph,OpenAddressesUK/morph,openaustralia/morph,openaustralia/morph,otherchirps/morph,otherchirps/morph,openaustralia/morph,openaustralia/morph,OpenAddressesUK/morph,otherchirps/morph,OpenAddressesUK/morph,otherchirps/morph,openaustralia/morph,openaustralia/morph,otherchirps/morph