Update swift version to 4.2

[aksswami]

Bump swift version to 4.2 and also increment pod version.

[ikesyo]

Thanks for the pr, but we would still like to keep Swift 4.0/4.1 compatiblity for a while. And also this is a breaking change so must be major version bump.

[aksswami]

I will update it for the major version bump. Can we have a swift-4.1 branch for swift 4.1 compatibility and master moved to latest swift version?

[norio-nomura]

Without any changes using the new features of Swift 4.2, what is the reason for updating to Swift 4.2?

[aksswami]

In my current project all pods are using Swift 4.2 except the Result and this gives me warning for upgrading the pods to Swift 4.2 . Yes, this is not an error/issue but still would like to clean things up.

[norio-nomura]

• Changing the SWIFT_VERSION of the Xcode project to 4.2.
  As far as I tested, I do not think it will be a breaking change since it can be built with Xcode 9.0.1, 9.1, 9.2, 9.3.1 and 9.4.1 even if it be changed.

I am not sure about changing podspec.

[Jenus]

please merge this pull request

[Jenus]

please merge 2 commits into antitypical:master. Thanks

[aksswami]

@norio-nomura I don't think updating the swift-version will be an issue as we are also bumping the pod version. Previous version use can be used with Swift 4, as per my understanding.

Is there anything else, which I should get correct to have this PR merged? As this seems to be request of many users.

[norio-nomura]

Could you please change SWIFT_VERSION in Project build settings instead of adding SWIFT_VERSION to each Target's build settings?

[aksswami]

I have changed the SWIFT_VERSION in Project Build settings to 4.2.

[adrianod1as]

+1

[larsschwegmann]

Any updates on this? These warnings are pretty annoying.

[norio-nomura]

Thanks!