Fix spelling in comments and documentation using codespell

Apply the utility from https://github.com/codespell-project/codespell/
to fix spelling issues in the headers under both include and interface
directories and add a file with a couple of exceptions.

The exact command line used was:

    $ codespell -w -I misc/scripts/codespell.ignore -i 3 in*

interface/wx/log.h

@@ -668,7 +668,7 @@ public:
         By default, the log messages are passed to the previously active log target.
         Calling this function with @false parameter disables this behaviour
         (presumably temporarily, as you shouldn't use wxLogChain at all otherwise) and
-        it can be reenabled by calling it again with @a passMessages set to @true.
+        it can be re-enabled by calling it again with @a passMessages set to @true.
     */
     void PassMessages(bool passMessages);