Make OpName callable, update definitions

Author: mtfishman

src/has_fermion_string.jl

@@ -1 +1,7 @@
-has_fermion_string(::OpName, ::SiteType) = false
+function has_fermion_string(n::OpName, t::SiteType)
+  n′ = alias(n)
+  if n == n′
+    return false
+  end
+  return has_fermion_string(n′, t)
+end