Many typo fixes from Karsten Weiss

Spotted using https://github.com/lucasdemarchi/codespell
diff --git a/Makefile.in b/Makefile.in
index 04e1c8e..8d33e53 100644
--- a/Makefile.in
+++ b/Makefile.in
@@ -1,4 +1,4 @@
-# uncomment if you run a non bourne compatable shell. Ie. csh
+# uncomment if you run a non bourne compatible shell. Ie. csh
 #SHELL = @SH@
 
 AUTORECONF=autoreconf