swift: add page (#2112)

pages/common/swift.md

@@ -0,0 +1,27 @@
+# swift
+
+> Create, run and build Swift projects.
+
+- Invoke the interactive interpreter (REPL):
+
+`swift`
+
+- Execute a program:
+
+`swift {{file.swift}}`
+
+- Start a new project with the package manager:
+
+`swift package init`
+
+- Generate an Xcode project file:
+
+`swift package generate-xcodeproj`
+
+- Update dependencies:
+
+`swift package update`
+
+- Compile project for release:
+
+`swift build -c release`