Allow to separate top-level script declarations and statements with semicolon

This fix allows to write one-liner scripts like "val x = 3; println(x)", which
were previously rejected by the parser.

compiler/psi/src/org/jetbrains/kotlin/parsing/KotlinExpressionParsing.java

@@ -1261,7 +1261,7 @@ public class KotlinExpressionParsing extends AbstractKotlinParsing {
             else if (at(RBRACE)) {
                 break;
             }
-            else if (!myBuilder.newlineBeforeCurrentToken()) {
+            else if (!isScriptTopLevel && !myBuilder.newlineBeforeCurrentToken()) {
                 String severalStatementsError = "Unexpected tokens (use ';' to separate expressions on the same line)";
 
                 if (atSet(STATEMENT_NEW_LINE_QUICK_RECOVERY_SET)) {