Strange formatting of comments

Unfortunately javadoc style multiline comments preceding a rule cause a strange formatting effect. The following rule is moved to just after the comment ending. Also, multiple single line comments are indented and extra lines are added.

```
grammar Funny;

/**
This is a funny grammar that confuses Antlr4Formatter
*/
test : 'a' 'b' 'c' test2 EOF;

//
// test number 2
//
test2 : '1' '2' '3';
```
turns into
```
grammar Funny;

/**
This is a funny grammar that confuses Antlr4Formatter
*/ test
: 'a' 'b' 'c' test2 EOF
;
//

// test number 2

//

test2
: '1' '2' '3'
;
```

This seems very odd to me. I'm not sure if this is intentional or not.

Reproduce the issue with the Funny grammar shown in the report, focusing on a Javadoc comment before a rule and consecutive single-line comments. Trace the Antlr4Formatter entry point that formats comments and rules; done means comments retain their placement and indentation without extra blank lines or a rule being joined to a comment terminator.

Written by the indexing model from the issue text.