Swift Package Manager Support for v. 1.5.0.

[eduardoperez-nbcuni]

Description

This PR implements Swift Package Manager support for the released version 1.5.0.

Change Notes

• Added new class Package.swift to implement the Swift Package manifest.
• Since SPM doesn't support Objective-C/Swift code on the same target, new internal targets for the Obj-C classes were created in the package manifest: HLSStringRef, HLSRapidParser, CMTimeMakeFromString, RapidParserMasterParseArray.
• All the new internal targets were added as dependencies for the main target mamba. (Which is the only target exposed to be implemented).
• There was a small re-structure in the folders containing Obj-C classes:
  1. Now the Obj-C classes are grouped in folders named Library.
  2. Library folders include an internal folder that contains symlinks files used to expose their public headers. More information about this in here. In the section PUBLIC INTERFACES
  3. Mamba.xcodeproj was modified to reflect those new folder structures.
• New class Exports.swift was created. This class exposes Objective-C public headers for Swift use. More information about this in here. In the section EXPOSING YOUR OBJC TO SWIFT USERS
• Due the "folder structure" nature of SPM, some imports were modified to reflect relative paths.

Pre-submission Checklist

• [x] I ran the unit tests locally before checking in.
• [x] I made sure there were no compiler warnings before checking in.
• [ ] I have written useful documentation for all public code.
• [ ] I have written unit tests for this new feature.

[CLAassistant]

All committers have signed the CLA.

[eduardoperez-nbcuni]

Most of my comments are about lessening the impact on the project by having SPM support (removing symlinks, removing preprocessor macros, removing double defines). Please give me feedback if they make supporting SPM impossible.

Also, we use the branch structure develop/main. develop is for work being done and it the "bleeding edge". main is for releases. PR's go into develop unless they represent a release.

In our project develop_1.x is the correct target for 1.x updates, if you could repoint your PR or close this one and make a new one, that would be helpful.

Thanks for the PR!

Thank you for your feedback, David. I have created a new PR that points to develop_1.x and I have applied the requested changes in here. I will close this one so we can focus on the new PR. Thank you!