UncheckedProperty for cmdProperty et al

* Properties that run an arbitrary command, such as cmdProperty
  and scriptProperty are converted to use UncheckedProperty, since
  they cannot tell on their own if the command truely made a change or not.
  (API Change)
  Transition guide:
  - When GHC complains about an UncheckedProperty, add:
  	`assume` MadeChange
  - Since these properties used to always return MadeChange, that
    change is always safe to make.
  - Or, if you know that the command should modifiy a file, use:
  	`changesFile` filename
* A few properties have had their Result improved, for example
  Apt.buldDep and Apt.autoRemove now check if a change was made or not.

1 files changed, 1 insertions, 0 deletions

diff --git a/src/Propellor/Property.hs b/src/Propellor/Property.hs
index f57fcaee..c57ef2f0 100644
--- a/src/Propellor/Property.hs
+++ b/src/Propellor/Property.hs
@@ -31,6 +31,7 @@ module Propellor.Property (
 	, changesFile
 	, checkResult
 	, Checkable
+	, assume
 ) where
 
 import System.Directory