Fix Swift 5 and Xcode 12.2 warnings

• Fixed Swift 5 compiler warnings. Thanks @valeriyvan !
• Updated project settings recommended by Xcode 12.2.

3.1.2

• SPM breakage fix for Xcode 11.4 beta and after. Thanks @thebluepotato for #107 .

3.1.1

• Swift Package Manager support for Xcode 11. Thanks @thebluepotato for #101 !

3.1.0

• Fuzi now supports defining custom prefix for non-default namespace for XPath queries! (#99) Thanks @mmenu-mantano!

Swift 5

• Swift 5 support.

Real final version for Swift 4.2.

• Fixed a bug that parses an HTML document with xmlReadMemory. This worked previously because the compiler used to treat convenience initializers in a polymorphic manner, which does not match the spec.

Final version for Swift 4.*

• Just leaving a final Swift 4.2 compatible version before switching to Swift 5.

2.1.0

• Added a throw version of xpath method to Queryable protocol so that there is now a way to see the error when you pass in an invalid XPath query string instead of just getting a silent empty result. The non-throw xpath method is still there so you don't need to change your code. Thanks @Parabak !
• Fixed all warnings in Xcode 9.3.

2.0.2

Removed module map for Xcode 9.3

2.0.1

• Disabled coverage to prevent potential AppStore rejection if using Carthage ( Thanks @mhmiles )
• Fixed firstChild crash bug when ns is specified for certain documents ( #70. Thanks @banjun )