utils.script: Add support for "open_mode" to support binary

Currently the "Script" only uses text mode to open files, let's allow to
set any mode by using "open_mode" to allow passing binary data, when
needed.
Signed-off-by: NLukáš Doktor <ldoktor@redhat.com>

avocado/utils/script.py

@@ -39,7 +39,7 @@ class Script(object):
     Class that represents a script.
     """
 
-    def __init__(self, path, content, mode=DEFAULT_MODE):
+    def __init__(self, path, content, mode=DEFAULT_MODE, open_mode='w'):
         """
         Creates an instance of :class:`Script`.
 
@@ -54,6 +54,7 @@ class Script(object):
         self.content = content
         self.mode = mode
         self.stored = False
+        self.open_mode = open_mode
 
     def __repr__(self):
         return '%s(path="%s", stored=%s)' % (self.__class__.__name__,
@@ -78,7 +79,7 @@ class Script(object):
         """
         dirname = os.path.dirname(self.path)
         utils_path.init_dir(dirname)
-        with open(self.path, 'w') as fd:
+        with open(self.path, self.open_mode) as fd:
             fd.write(self.content)
             os.chmod(self.path, self.mode)
             self.stored = True
@@ -104,7 +105,7 @@ class TemporaryScript(Script):
     Class that represents a temporary script.
     """
 
-    def __init__(self, name, content, prefix='avocado_script', mode=DEFAULT_MODE):
+    def __init__(self, name, content, prefix='avocado_script', mode=DEFAULT_MODE, open_mode='w'):
         """
         Creates an instance of :class:`TemporaryScript`.
 
@@ -124,6 +125,7 @@ class TemporaryScript(Script):
         self.content = content
         self.mode = mode
         self.stored = False
+        self.open_mode = open_mode
 
     def __del__(self):
         self.remove()