Rename package to swift-mustache (#27)

* Rename package to swift-mustache

* Update CI

Sources/Mustache/Template.swift

@@ -0,0 +1,47 @@
+//===----------------------------------------------------------------------===//
+//
+// This source file is part of the Hummingbird server framework project
+//
+// Copyright (c) 2021-2021 the Hummingbird authors
+// Licensed under Apache License v2.0
+//
+// See LICENSE.txt for license information
+// See hummingbird/CONTRIBUTORS.txt for the list of Hummingbird authors
+//
+// SPDX-License-Identifier: Apache-2.0
+//
+//===----------------------------------------------------------------------===//
+
+/// Class holding Mustache template
+public struct MustacheTemplate: Sendable {
+    /// Initialize template
+    /// - Parameter string: Template text
+    /// - Throws: MustacheTemplate.Error
+    public init(string: String) throws {
+        self.tokens = try Self.parse(string)
+    }
+
+    /// Render object using this template
+    /// - Parameter object: Object to render
+    /// - Returns: Rendered text
+    public func render(_ object: Any, library: MustacheLibrary? = nil) -> String {
+        self.render(context: .init(object, library: library))
+    }
+
+    internal init(_ tokens: [Token]) {
+        self.tokens = tokens
+    }
+
+    enum Token: Sendable {
+        case text(String)
+        case variable(name: String, transform: String? = nil)
+        case unescapedVariable(name: String, transform: String? = nil)
+        case section(name: String, transform: String? = nil, template: MustacheTemplate)
+        case invertedSection(name: String, transform: String? = nil, template: MustacheTemplate)
+        case inheritedSection(name: String, template: MustacheTemplate)
+        case partial(String, indentation: String?, inherits: [String: MustacheTemplate]?)
+        case contentType(MustacheContentType)
+    }
+
+    var tokens: [Token]
+}