Add impl to convert a ZipError to a io::Error

Resolves #4

Cargo.toml

@@ -1,7 +1,7 @@
 [package]
 
 name = "zip"
-version = "0.1.5"
+version = "0.1.6"
 authors = ["Mathijs van de Nes <git@mathijs.vd-nes.nl>"]
 license = "MIT"
 repository = "https://github.com/mvdnes/zip-rs.git"

src/result.rs

@@ -1,8 +1,9 @@
 //! Error types that can be emitted from this library
 
-use std::io;
+use std::convert;
 use std::error;
 use std::fmt;
+use std::io;
 
 /// Generic result type with ZipError as its error variant
 pub type ZipResult<T> = Result<T, ZipError>;
@@ -45,7 +46,7 @@ impl ZipError
     }
 }
 
-impl ::std::convert::From<io::Error> for ZipError
+impl convert::From<io::Error> for ZipError
 {
     fn from(err: io::Error) -> ZipError
     {
@@ -53,6 +54,14 @@ impl ::std::convert::From<io::Error> for ZipError
     }
 }
 
+impl convert::From<ZipError> for io::Error
+{
+    fn from(err: ZipError) -> io::Error
+    {
+        io::Error::new(io::ErrorKind::Other, err)
+    }
+}
+
 impl fmt::Display for ZipError
 {
     fn fmt(&self, fmt: &mut fmt::Formatter) -> Result<(), fmt::Error>