Support for Linux Platform

[noppoMan]

Hi, I'm just using this for parsing hal+json content in my own library and then, I saw following 2 compiling errors on Swift version 3.1 (swift-3.1-RELEASE) Target: x86_64-unknown-linux-gnu environment.

error: incorrect argument label in call (have 'pattern:', expected 'coder:')
      static let expression = try! NSRegularExpression(pattern: "\\{.+\\}")
                                                      ^~~~~~~~
                                                       coder

error: missing argument for parameter 'options' in call
    return Templated.expression.numberOfMatches(in: href, range: range) > 0
                                                        ^
                                                        , options: <#NSMatchingOptions#>
Foundation.NSRegularExpression:4:17: note: 'numberOfMatches(in:options:range:)' declared here
    public func numberOfMatches(in string: String, options: Foundation.NSMatchingOptions, range: Foundation.NSRange) -> Int

The Linux version of NSRegularExpression and numberOfMatches seems to be unable to omit options label.

So I tried to add options labels and it worked fine on Linux. Here is testing results
If you'd like it, please merge this. Anyways, Thanks for creating such a great library.

[Yasumoto]

@royratcliffe howdy! Any chance this could get merged? If so I've got a PR that I'd love to merge in here upstream: noppoMan#1