Fix RSA.import_key (fixes #101)

Apparently "import_key" only exists in newer versions (as an alias to
"importKey"). "importKey" works in all versions ...

CHANGELOG.md

@@ -69,4 +69,4 @@ List of changes since the fork of Apprentice Harper's repository:
 
 ## Fixes on master (not yet released):
 
-- (None)
+- Fix a bug introduced with #48 that breaks DeDRM'ing on Calibre 4 (fixes #101).

DeDRM_plugin/ineptepub.py

@@ -302,7 +302,7 @@ def decryptBook(userkey, inpath, outpath):
 
             if len(bookkey) != 64:
                 # Normal or "hardened" Adobe ADEPT
-                rsakey = RSA.import_key(userkey) # parses the ASN1 structure
+                rsakey = RSA.importKey(userkey) # parses the ASN1 structure
                 bookkey = base64.b64decode(bookkey)
                 if int(keytype, 10) > 2:
                     bookkey = removeHardening(rights, keytype, bookkey)

DeDRM_plugin/ineptpdf.py

@@ -1669,7 +1669,7 @@ class PDFDocument(object):
 
     def initialize_ebx_inept(self, password, docid, param):
         self.is_printable = self.is_modifiable = self.is_extractable = True
-        rsakey = RSA.import_key(password) # parses the ASN1 structure
+        rsakey = RSA.importKey(password) # parses the ASN1 structure
         length = int_value(param.get('Length', 0)) // 8
         rights = codecs.decode(param.get('ADEPT_LICENSE'), 'base64')
         rights = zlib.decompress(rights, -15)