Tweak docs building

Trying to save the warnings to a file only works if the directory
exists.  Also fix digfort docs error.

.gitignore

@@ -21,7 +21,7 @@ buntu
 build/VC2010
 
 # Sphinx generated documentation
-docs/_*/
+docs/_*
 docs/html/
 
 #except for the real one

CMakeLists.txt

@@ -224,7 +224,7 @@ if (BUILD_DOCS)
       -c "${CMAKE_CURRENT_SOURCE_DIR}/docs"
       "${CMAKE_CURRENT_SOURCE_DIR}"
       "${CMAKE_CURRENT_SOURCE_DIR}/docs/html"
-      -w "${CMAKE_CURRENT_SOURCE_DIR}/docs/_build/sphinx-warnings.txt"
+      -w "${CMAKE_CURRENT_SOURCE_DIR}/docs/_sphinx-warnings.txt"
     DEPENDS ${SPHINX_DEPS}
     COMMENT "Building HTML documentation with Sphinx"
   )

scripts/digfort.rb

@@ -10,10 +10,10 @@ Your plan should be stored in a .csv file like this::
 
     # this is a comment
     d;d;u;d;d;skip this tile;d
-    d;d;d;i
+    d;d;d;j
 
 Available tile shapes are named after the 'dig' menu shortcuts:
-``d`` for dig, ``u`` for upstairs, ``d`` downstairs, ``i`` updown,
+``d`` for dig, ``u`` for upstairs, ``d`` downstairs, ``j`` updown,
 ``h`` channel, ``r`` upward ramp, ``x`` remove designation.
 Unrecognized characters are ignored (eg the 'skip this tile' in the sample).