Fix crash in file creation

A crash in file creation (caused by a race) was detected in a monkey test,
so test if path is valid before creating a file.

Signed-off-by: Claudio Matsuoka <cmatsuoka@gmail.com>
Fix crash in mod list when list is empty

Signed-off-by: Claudio Matsuoka <cmatsuoka@gmail.com>
Update changelog

Signed-off-by: Claudio Matsuoka <cmatsuoka@gmail.com>