Add support for Swift 3.0

Tests/StencilTests/LexerSpec.swift

@@ -0,0 +1,50 @@
+import Spectre
+import Stencil
+
+
+func testLexer() {
+  describe("Lexer") {
+    $0.it("can tokenize text") {
+      let lexer = Lexer(templateString: "Hello World")
+      let tokens = lexer.tokenize()
+
+      try expect(tokens.count) == 1
+      try expect(tokens.first) == .text(value: "Hello World")
+    }
+
+    $0.it("can tokenize a comment") {
+      let lexer = Lexer(templateString: "{# Comment #}")
+      let tokens = lexer.tokenize()
+
+      try expect(tokens.count) == (1)
+      try expect(tokens.first) == .comment(value: "Comment")
+    }
+
+    $0.it("can tokenize a variable") {
+      let lexer = Lexer(templateString: "{{ Variable }}")
+      let tokens = lexer.tokenize()
+
+      try expect(tokens.count) == 1
+      try expect(tokens.first) == .variable(value: "Variable")
+    }
+
+    $0.it("can tokenize a mixture of content") {
+      let lexer = Lexer(templateString: "My name is {{ name }}.")
+      let tokens = lexer.tokenize()
+
+      try expect(tokens.count) == 3
+      try expect(tokens[0]) == Token.text(value: "My name is ")
+      try expect(tokens[1]) == Token.variable(value: "name")
+      try expect(tokens[2]) == Token.text(value: ".")
+    }
+
+    $0.it("can tokenize two variables without being greedy") {
+      let lexer = Lexer(templateString: "{{ thing }}{{ name }}")
+      let tokens = lexer.tokenize()
+
+      try expect(tokens.count) == 2
+      try expect(tokens[0]) == Token.variable(value: "thing")
+      try expect(tokens[1]) == Token.variable(value: "name")
+    }
+  }
+}