Refactor load_yajl

To reduce code duplication introduced by adding windows support in
commit 117166f.

List of file names is generated using a list comprehension so that
the unique windows file name can be appended. Consequently, the
list of file names can be iterated over and two separate cases are
not needed.

Author: sproberts92

yajl/yajl_common.py

@@ -32,19 +32,14 @@ def load_yajl():
     :returns: The yajl shared object
     :raises OSError: when libyajl cannot be loaded
     '''
-    for ftype in '', '.so', '.dylib':
-        yajlso = 'libyajl%s' %(ftype)
+    fnames = ['libyajl%s' %(t) for t in ['', '.so', '.dylib']] + ['yajl.dll']
+
+    for yajlso in fnames:
         try:
             return cdll.LoadLibrary(yajlso)
         except OSError:
             pass
 
-    yajlso = 'yajl.dll'
-    try:
-        return cdll.LoadLibrary(yajlso)
-    except OSError:
-        pass
-
     raise OSError('Yajl shared object cannot be found. '
         'Please install Yajl and confirm it is on your shared lib path.')