Update package to use github version of GMPLib.

Swift Package Manager version.

Keep up Carthage!

Double value

beta 4 update

Version 0.4.1. Minimum deployment target iOS 8

Multiplatform

Merge branch 'include-lib' as it fixes gmplib inclusion problems.

Change Xcode lib path to $(SRCROOT)/GMPLib.

Add gitignore. Change module path to use non-specific version.