allow globbing, and extract queries from .go files

generate/testdata/queries/QueryWithAlias.graphql.go

@@ -0,0 +1,35 @@
+package test
+
+// Code generated by github.com/Khan/genqlient, DO NOT EDIT.
+
+import (
+	"github.com/Khan/genqlient/graphql"
+)
+
+type QueryWithAliasResponse struct {
+	User QueryWithAliasUser
+}
+
+type QueryWithAliasUser struct {
+	ID string
+}
+
+func QueryWithAlias(
+	client graphql.Client,
+) (*QueryWithAliasResponse, error) {
+	var retval QueryWithAliasResponse
+	err := client.MakeRequest(
+		nil,
+		"QueryWithAlias",
+		`
+query QueryWithAlias {
+	User: user {
+		ID: id
+	}
+}
+`,
+		&retval,
+		nil,
+	)
+	return &retval, err
+}