crecord: conditionalize the imports that are not available on Windows

'fcntl', 'termios' and 'wcurses' are not available on the default Windows python
installation, and importing them caused widespread carnage in the test suite.
There were 29 different changed test files (on top of unrelated errors), mostly
in the form of an ImportError.

The failures weren't related to actual crecord use, and followed the import
chain:

    'localrepo' -> 'subrepo' -> 'cmdutil' -> 'crecord' -> 'fcntl'

mercurial/crecord.py

@@ -12,7 +12,7 from i18n import _
 import patch as patchmod
 import util, encoding
 
-import os, re, sys, fcntl, struct, termios, signal, tempfile, locale, cStringIO
+import os, re, sys, struct, signal, tempfile, locale, cStringIO
 
 # This is required for ncurses to display non-ASCII characters in default user
 # locale encoding correctly.  --immerrr
@@ -20,10 +20,14 locale.setlocale(locale.LC_ALL, '')
 
 # os.name is one of: 'posix', 'nt', 'dos', 'os2', 'mac', or 'ce'
 if os.name == 'posix':
-    import curses
+    import curses, fcntl, termios
 else:
     # I have no idea if wcurses works with crecord...
-    import wcurses as curses
+    try:
+        import wcurses as curses
+    except ImportError:
+        # wcurses is not shipped on Windows by default
+        pass
 
 try:
     curses

tests/test-module-imports.t

@@ -21,6 +21,9 hidden by deduplication algorithm in the
 these may expose other cycles.
 
   $ hg locate 'mercurial/**.py' | sed 's-\\-/-g' | xargs python "$import_checker"
+  mercurial/crecord.py mixed imports
+     stdlib:    fcntl, termios
+     relative:  curses
   mercurial/dispatch.py mixed imports
      stdlib:    commands
      relative:  error, extensions, fancyopts, hg, hook, util