Bump Zone.js to remove warnings when using angular >=6.

[d0x]

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Description of the PR

Fixed #1506 . Bump Zone.js peer dependency. Angular 6 and 7 is using Zone.js 0.8.26. I tested zone.js 0.8.26 in our environment with Angular 6.

Since it shouldn't break anything, the current master branch is correct, or?

@Committee: I used the syntax ^0.7.6 || ^0.8.26 to support a wider range of angular versions. What do you think about this?

And why ./bin/typescript-angular-petstore-all.sh doesn't put this syntax into the generated package.jsons?

[macjohnny]

looks good to me.

[macjohnny]

I think the zone.js dependency could be removed from the peerDependencies, since it will be included in angular projects anyway.

[macjohnny]

I just saw that the angular 2/4 samples are also affected, this should not be the case, since the zone.js dependency should remain 0.7.6 int that case

[d0x]

@macjohnny ok, what do you suggest?

Should I remove the zonejs dependencies since we already depend on angular/http?

And regarding the change on angular2/4 samples, what should I do there? I just regenerated all the angular samples with ^0.7.6 || ^0.8.26. That shouldn't be a problem for angular2/4. Do you agree? We don't have a switch to deliver different templates for different angular versions.

[macjohnny]

@d0x I suggest to remove the peerDependency on zone.js. Concerning the 2/4 compatibility, I think ^0.7.6 || ^0.8.26 is a good option, as the dependency will be given by angular anyway, so npm will find the zone.js version that matches all constraints

[d0x]

Ok, I think we have it then.

I removed it and regenerated the templates.

[wing328]

@d0x thanks for the PR, which has been included in the v3.3.4 release: https://twitter.com/oas_generator/status/1068772409795207168