When apps are not installed from Google Play, do not export links to Google Play

[artfulrobot]

Although the checkbox for "always link to Google play" was not checked, my app list exports links to Google even for my f-droid installed apps.

[RokeJulianLockhart]

http://github.com/onyxbits/listmyaps/issues/13#issue-934425269

Y̶o̶u̶r̶ ̶d̶e̶s̶c̶r̶i̶p̶t̶i̶o̶n̶ ̶o̶f̶ ̶t̶h̶i̶s̶ ̶i̶s̶s̶u̶e̶ ̶a̶n̶d̶ ̶t̶h̶e̶ ̶i̶s̶s̶u̶e̶ ̶a̶r̶e̶ ̶q̶u̶i̶t̶e̶ ̶d̶i̶f̶f̶e̶r̶e̶n̶t̶.̶ ̶O̶n̶e̶ ̶i̶s̶ ̶o̶n̶e̶ ̶f̶e̶a̶t̶u̶r̶e̶-̶r̶e̶q̶u̶e̶s̶t̶,̶ ̶w̶h̶e̶r̶e̶a̶s̶ ̶o̶n̶e̶ ̶i̶s̶ ̶o̶n̶e̶ ̶p̶r̶o̶b̶l̶e̶m̶.̶

[artfulrobot]

@BEEDELLROKEJULIANLOCKHART I have updated the title.

1. install app A from F-droid
2. install app B from Google Play
3. Use listmyapps to export a list of apps, and do NOT check the "always link to Google play"

Expectation:

App A is listed with link to F-droid (or at least not a link to Google Play)
App B is listed with link to Google Play.

Hope that's clearer.