Using dot in ScalarFunctions name value cause failures
We are wring a custom functions like `@ScalarFunction(value = "pretradedate", alias = "default.pretradedate")`. When select on `default.pretradedate`, it throws error
```
io.prestosql.spi.PrestoException: line 1:1: Function default.pretradedate not registered

	at io.prestosql.sql.analyzer.ExpressionAnalyzer$Visitor.visitFunctionCall(ExpressionAnalyzer.java:878)
	at io.prestosql.sql.analyzer.ExpressionAnalyzer$Visitor.visitFunctionCall(ExpressionAnalyzer.java:316)
	at io.prestosql.sql.tree.FunctionCall.accept(FunctionCall.java:110)
	at io.prestosql.sql.tree.StackableAstVisitor.process(StackableAstVisitor.java:26)
	at io.prestosql.sql.analyzer.ExpressionAnalyzer$Visitor.process(ExpressionAnalyzer.java:339)
	at io.prestosql.sql.analyzer.ExpressionAnalyzer.analyze(ExpressionAnalyzer.java:276)
	at io.prestosql.sql.ExpressionTestUtils.planExpression(ExpressionTestUtils.java:92)
	at io.prestosql.operator.scalar.FunctionAssertions.createExpression(FunctionAssertions.java:641)
	at io.prestosql.operator.scalar.FunctionAssertions.executeProjectionWithAll(FunctionAssertions.java:480)
	at io.prestosql.operator.scalar.FunctionAssertions.selectUniqueValue(FunctionAssertions.java:295)
	at io.prestosql.operator.scalar.FunctionAssertions.selectSingleValue(FunctionAssertions.java:290)
	at io.prestosql.operator.scalar.FunctionAssertions.assertFunction(FunctionAssertions.java:253)
	at io.prestosql.operator.scalar.AbstractTestFunctions.assertFunction(AbstractTestFunctions.java:91)
	at cn.com.gf.bdp.presto.udf.tradingday.TradeDateFunctionTest.testPretradeDate(TradeDateFunctionTest.java:56)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.lang.reflect.Method.invoke(Method.java:498)
	at org.testng.internal.MethodInvocationHelper.invokeMethod(MethodInvocationHelper.java:104)
	at org.testng.internal.Invoker.invokeMethod(Invoker.java:645)
	at org.testng.internal.Invoker.invokeTestMethod(Invoker.java:851)
	at org.testng.internal.Invoker.invokeTestMethods(Invoker.java:1177)
	at org.testng.internal.TestMethodWorker.invokeTestMethods(TestMethodWorker.java:129)
	at org.testng.internal.TestMethodWorker.run(TestMethodWorker.java:112)
	at org.testng.TestRunner.privateRun(TestRunner.java:756)
	at org.testng.TestRunner.run(TestRunner.java:610)
	at org.testng.SuiteRunner.runTest(SuiteRunner.java:387)
	at org.testng.SuiteRunner.runSequentially(SuiteRunner.java:382)
	at org.testng.SuiteRunner.privateRun(SuiteRunner.java:340)
	at org.testng.SuiteRunner.run(SuiteRunner.java:289)
	at org.testng.SuiteRunnerWorker.runSuite(SuiteRunnerWorker.java:52)
	at org.testng.SuiteRunnerWorker.run(SuiteRunnerWorker.java:86)
	at org.testng.TestNG.runSuitesSequentially(TestNG.java:1293)
	at org.testng.TestNG.runSuitesLocally(TestNG.java:1218)
	at org.testng.TestNG.runSuites(TestNG.java:1133)
	at org.testng.TestNG.run(TestNG.java:1104)
	at org.testng.IDEARemoteTestNG.run(IDEARemoteTestNG.java:72)
	at org.testng.RemoteTestNGStarter.main(RemoteTestNGStarter.java:123)
Caused by: io.prestosql.spi.PrestoException: Function default.pretradedate not registered
	at io.prestosql.metadata.FunctionRegistry.resolveFunction(FunctionRegistry.java:706)
	at io.prestosql.metadata.MetadataManager.lambda$resolveFunction$19(MetadataManager.java:1312)
	at java.util.Optional.orElseGet(Optional.java:267)
	at io.prestosql.metadata.MetadataManager.resolveFunction(MetadataManager.java:1312)
	at io.prestosql.sql.analyzer.ExpressionAnalyzer$Visitor.visitFunctionCall(ExpressionAnalyzer.java:866)
	... 37 more
```
Presto version: 323