remove command, which supports dry runs (so does create)

include/cellar.hpp

@@ -13,6 +13,7 @@ namespace cellar {
 
     extern bottles::Bottle active_bottle;
     
+    extern bool dryrun;
     extern bool verbose;
 }
 

include/fs.hpp

@@ -9,9 +9,14 @@ using namespace std;
 
 namespace cellar {
 	namespace fs {
+        typedef void (*CopyCallbackFunc)(string,string); 
+        typedef void (*RemoveCallbackFunc)(string); 
 		extern vector<string> listdir(string path);
+        
         extern bool recursive_copy(string, string);
         extern bool recursive_remove(string);
+        extern bool recursive_copy(string, string, CopyCallbackFunc);
+        extern bool recursive_remove(string, RemoveCallbackFunc);
 	}
 }