PNG exporst do not appear to have png extension added to saved names.

What steps will reproduce the problem?
1. Select export png
2. Type name of save file with no extension "junk"
3. Files appear in save directory as "junk" instead of "junk.png"

What is the expected output? What do you see instead?
Expected to see default extension of "png" automatically appended to saved name
Whenever possible, please attach the latest log file. It will
provide valuable information when trying to reproduce and locate the
problem. Log files can be found in the log directory under the main
application directory and are marked with date and time.

What version of the product are you using? On what operating system?
beta 3.7.0
win xp sp3

Please provide any additional information below.

Original issue reported on code.google.com by timmath...@gmail.com on 22 Jun 2012 at 4:50

Merged into: #8

stephen-hill / diy-layout-creator

PNG exporst do not appear to have png extension added to saved names. #146