Rename source UFOs

This uses a more standard naming scheme for the source UFOs. No idea
why it wasn't used before, but it's been bothering me for a while.
Wanted to do this while there still aren't really any meaningful
changes in the source (just hard-to-read bulk changes).

scripts/build-v2.py

@@ -31,9 +31,9 @@ BASEDIR = os.path.abspath(
 
 # Masters
 
-rg = Master("%s/src/v2/Roboto_Regular.ufo" % BASEDIR)
-bd = Master("%s/src/v2/Roboto_Bold.ufo" % BASEDIR)
-th = Master("%s/src/v2/Roboto_Thin.ufo" % BASEDIR)
+rg = Master("%s/src/v2/Roboto-Regular.ufo" % BASEDIR)
+bd = Master("%s/src/v2/Roboto-Bold.ufo" % BASEDIR)
+th = Master("%s/src/v2/Roboto-Thin.ufo" % BASEDIR)
 
 lessCondensed = (
     "plusminus bracketleft bracketright dieresis macron "