Separate schema files should work

When abstract schema is written in a separate file, reading schemas
process terminates in failure. Fix bug and tests to try read
multiple schema files.

db/db_test.go

@@ -64,6 +64,7 @@ var _ = Describe("Database operation test", func() {
 		)
 
 		BeforeEach(func() {
+			Expect(manager.LoadSchemaFromFile("../tests/test_abstract_schema.yaml")).To(Succeed())
 			Expect(manager.LoadSchemaFromFile("../tests/test_schema.yaml")).To(Succeed())
 			networkSchema, ok = manager.Schema("network")
 			Expect(ok).To(BeTrue())
@@ -258,6 +259,7 @@ var _ = Describe("Database operation test", func() {
 		BeforeEach(func() {
 			conn = "test.db"
 			dbType = "sqlite3"
+			Expect(manager.LoadSchemaFromFile("../tests/test_abstract_schema.yaml")).To(Succeed())
 			Expect(manager.LoadSchemaFromFile("../tests/test_schema.yaml")).To(Succeed())
 		})
 

db/sql/sql_test.go

@@ -50,7 +50,7 @@ var _ = Describe("Sql", func() {
 		sqlConn = dbc.(*DB)
 		Expect(err).ToNot(HaveOccurred())
 		Expect(manager.LoadSchemasFromFiles(
-			"../../etc/schema/gohan.json", "../../tests/test_schema.yaml")).To(Succeed())
+			"../../etc/schema/gohan.json", "../../tests/test_abstract_schema.yaml", "../../tests/test_schema.yaml")).To(Succeed())
 		db.InitDBWithSchemas(dbType, conn, true, false)
 
 		// Insert fixture data