Add newline between exports, which are multiline because of comments

[awalterschulze]

-export([ drop/4 %% comment
        ]).

%% Another comment
-export([ a/1,
        b/1
]).

is currently formatted to

%% comment
-export([drop/4]).
%% Another comment
-export([a/1, b/1]).

But there seems to be newline missing between the two exports as they are technically both multiline.

[awalterschulze]

The reason for automatically adding a newline, given a comment, is that then the following

% bla
-define(FOO, "foo").
-define(BAR, "bar").
-define(BAZ, [
    "a"
]).

would be formatted to

% bla
-define(FOO, "foo").

-define(BAR, "bar").
-define(BAZ, [
    "a"
]).

But we can consider preserving new lines as then this would allow users to group defines manually

-define(FOO1, "foo").
-define(FOO2, "foo").

-define(NOTFOO, "bar").
-define(NOTFOO2, "bar").