Merge pull request swiftlang#124 from groue/pr_GRDB

GRDB.swift and Swift 4

Author: lplarson

projects.json

@@ -486,6 +486,10 @@
     "path": "GRDB.swift",
     "branch": "master",
     "compatibility": [
+      {
+        "version": "4.0",
+        "commit": "58e05d13d1e5b42c70c6dd36d64cf1a44fabbb45"
+      },
       {
         "version": "3.1",
         "commit": "ba8375adb120a9c67de8cc8f420c934581a82e3b"