Add bundle_name attribute to all bundling rules to override target name

[allevato]

Sometimes you don't want to use the target's name as the bundle's name, so we should add an optional bundle_name attribute that lets the user override that.

For example, currently this produces Foo.app and it can't be changed:

ios_application(
    name = "Foo",
    ...
)

So we should add this to get SomethingOtherThanFoo.app (note that the extension is still determined by the rule):

ios_application(
    name = "Foo",
    bundle_name = "SomethingOtherThanFoo",
    ...
)

[rahul-malik]

@allevato - Any sense of when this might be available? I'm currently trying to build a workaround at the moment for this issue.

[allevato]

@rahul-malik This is done now in master for applications/extensions/frameworks. It won't work yet for objc_bundle_library targets.