Many typo fixes from Karsten Weiss

Spotted using https://github.com/lucasdemarchi/codespell
diff --git a/TODO b/TODO
index f22c7e2..771162b 100644
--- a/TODO
+++ b/TODO
@@ -57,10 +57,10 @@
 - Replace the whole u_intXX_t evilness in acconfig.h with something better???
  - Do it in configure.ac
 
-- Consider splitting the u_intXX_t test for sys/bitype.h  into seperate test
+- Consider splitting the u_intXX_t test for sys/bitype.h  into separate test
   to allow people to (right/wrongfully) link against Bind directly.
 
-- Consider splitting configure.ac into seperate files which do logically
+- Consider splitting configure.ac into separate files which do logically
   similar tests. E.g move all the type detection stuff into one file,
   entropy related stuff into another.