add -Wall and a couple of other warning GHC options to .cabal file

ldap-client.cabal

@@ -25,6 +25,11 @@ source-repository head
   tag:      0.1.0
 
 library
+  ghc-options:
+    -Wall
+    -fwarn-incomplete-uni-patterns
+    -fwarn-incomplete-record-updates
+    -fwarn-unrecognised-pragmas
   default-language:
     Haskell2010
   hs-source-dirs:
@@ -56,6 +61,11 @@ library
     , text
 
 test-suite spec
+  ghc-options:
+    -Wall
+    -fwarn-incomplete-uni-patterns
+    -fwarn-incomplete-record-updates
+    -fwarn-unrecognised-pragmas
   default-language:
     Haskell2010
   type: