added working transactions. still not atomic

src/runtime/haskell/pgf2.cabal

@@ -22,6 +22,7 @@ extra-source-files:
 library
   exposed-modules:
     PGF2,
+    PGF2.Transactions,
     PGF2.Internal,
     -- backwards compatibility API:
     PGF
@@ -53,3 +54,12 @@ test-suite basic
     random,
     directory,
     pgf2
+
+test-suite transactions
+  type: exitcode-stdio-1.0
+  main-is: tests/transactions.hs
+  default-language: Haskell2010
+  build-depends:
+    base,
+    HUnit,
+    pgf2