Help cleanup

Large list of changes, including formatting and typos for most commands.

More substantive changes have been made to alias, bind, block, break,
builtin, case, cd, commandline, count, else, emit, fish_config, funced,
function, functions, history, math, mimedb, nextd, not, popd, prevd,
pushd, pwd, random, read, set, set_color, switch, test, trap, type,
ulimit, umask, and while.

doc_src/funced.txt

@@ -5,13 +5,14 @@
 
 \subsection funced-description Description
 
-Use the funced command to edit the definition of a function. If there is no
-function with the name specified, a skeleton function is inserted. If the
-function exists, its definition will be shown in your editor or on the command
-line.
+\c funced provides an interface to edit the definition of the function
+<code>NAME</code>.
 
-By default, funced edits functions using the text editor in your $EDITOR
-variable, if set; otherwise it uses the built-in editor.
+If the \c $EDITOR environment variable is set, it will be used as the program
+to edit the function. Otherwise, a built-in editor will be used.
+
+If there is no function called \c NAME a new function will be created with
+the specified name
 
 - <code>-e command</code> or <code>--editor command</code> Open the function
   body inside the text editor given by the command (for example, "vi"). The