Description:
------------
It looks like the parser thinks that >no< is a boolean value, 
even when it's a key, not a value.

Reproduce code:
---------------
Feed the yaml below to spyc_load()


FILES:
  class: JavaFFS
  sourcePattern: %GROUPROOT%/freecol/trunk/FreeColMessages_%CODE%.properties
  definitionFile: %GROUPROOT%/freecol/trunk/FreeColMessages.properties
  targetPattern: freecol/FreeColMessages_%CODE%.properties
  codeMap:
    cs:    cs_CZ
    es:    es_ES
    it:    it_IT
    no:    nb_NO
    pl:    pl_PL
    sv:    sv_SE
    nl-be: nl_BE
    en-gb: en_GB
    en-us: en_US
    pt:    pt_PT
    pt-br: pt_BR
    zh-hans: zh_CN
<

Expected result:
----------------
--- yaml-test-syck-pecl.txt     2011-03-08 14:21:52.636297886 
+0000
+++ yaml-test-syck.txt  2011-03-08 14:21:52.384297881 +0000
@@ -82,6 +82,7 @@
           'es' => 'es_ES',
           'it' => 'it_IT',
           'nl-be' => 'nl_BE',
+          'no' => 'nb_NO',
           'pl' => 'pl_PL',
           'pt' => 'pt_PT',
           'pt-br' => 'pt_BR',


Actual result:
--------------
The whole entry with key 'no' is missing.