THRIFT-2628/2689

client: erlang
patch: talentdeficit (alisdair sullivan)

generates idiomatic erlang names for structs, constants, module names
and records

adds the 'legacynames' generator option to preserve pre-0.9.2 naming
conventions
THRIFT-1191

client: erlang
patch: alisdair sullivan

test case for thrift-1191