Add missing imports

Author: p2

SQLite/Core/Connection.swift

@@ -22,6 +22,7 @@
 // THE SOFTWARE.
 //
 
+import Foundation
 import Dispatch
 #if SQLITE_SWIFT_STANDALONE
 import sqlite3

SQLite/Typed/CoreFunctions.swift

@@ -22,6 +22,9 @@
 // THE SOFTWARE.
 //
 
+import Foundation
+
+
 extension ExpressionType where UnderlyingType : Number {
 
     /// Builds a copy of the expression wrapped with the `abs` function.