Remove BlackBerry from the default platforms for new projects

Because I don't have BlackBerry configured on my system, I get an error when attempting to start triple:

```
(~/Documents/Titanium_Studio_Workspace) ≫ triple
[creating app]
[ERROR] Invalid platform: blackberry

[ERROR] Invalid "--platforms" value "android,blackberry,ios,ipad,iphone,mobileweb"

[ERROR] Invalid platform: blackberry

[ERROR] Invalid "--platforms" value "android,blackberry,ios,ipad,iphone,mobileweb"
```
I tried a couple of ways to pass in the target platform. There's probably a way. But for now, since Triple doesn't support BlackBerry, the easiest way was to remove it from the defaults for new projects.