Enable spell checking (#563)

* add spellchecking

* improve spelling

* improve spelling config

* extend word list

* improve spelling

* improve spelling

* escalate warning in spell check to failure

* fix spelling

* fix spelling

* add plural

* Update doc/spelling_wordlist.txt

* do not stop on warning

* require newest sphinxcontrib spelling

* remove old comment

* add authors as single line entry to spelling list

* reenable stop on warning

src/escpos/magicencode.py

@@ -28,15 +28,9 @@ class Encoder(object):
 
     Note: To determine the code page, it needs to do the conversion, and
     thus already knows what the final byte in the target encoding would
-    be. Nevertheless, the API of this class doesn't return the byte.
+    be. Nevertheless, the API of this class does not return the byte.
 
     The caller use to do the character conversion itself.
-
-        $ python -m timeit -s "{u'ö':'a'}.get(u'ö')"
-        100000000 loops, best of 3: 0.0133 usec per loop
-
-        $ python -m timeit -s "u'ö'.encode('latin1')"
-        100000000 loops, best of 3: 0.0141 usec per loop
     """
 
     def __init__(self, codepage_map):
@@ -117,7 +111,7 @@ class Encoder(object):
         return codepage_char_map
 
     def can_encode(self, encoding, char):
-        """Determine if a character is encodeable in the given code page.
+        """Determine if a character is encodable in the given code page.
 
         :param encoding: The name of the encoding.
         :param char: The character to attempt to encode.
@@ -171,7 +165,7 @@ class Encoder(object):
         1. code pages that we already tried before; there is a good
            chance they might work again, reducing the search space,
            and by re-using already used encodings we might also
-           reduce the number of codepage change instructiosn we have
+           reduce the number of codepage change instruction we have
            to send. Still, any performance gains will presumably be
            fairly minor.