The product_name of target shouldn't be the same as the same of `target`

For example, [GRDB.swift.podspec](https://github.com/groue/GRDB.swift/blob/master/GRDB.swift.podspec). The target name is 'GRDB.swift`, but the product module name should be `GRDB`.

My project depends on `GRDB.swift`, after `pod install` , in the `GRDB.swift` target in the `Pods.xcodeproj` file, the product name is 'GRDB`

But in this repo, when creating a new target, the target name is the same as the target product name . [code here](https://github.com/CocoaPods/Xcodeproj/blob/dac33d249ede1af24c8391e9a2c8b803cb316c4b/lib/xcodeproj/project/project_helper.rb#L49)

Cocoapods version: 1.6.1