:Add txt extension to githubbub files

Will ensure that proper MIME type is served to the client.

Makefile

@@ -21,7 +21,7 @@ pages := $(patsubst %.pg, %.html, \
 pages_md := $(patsubst %.md, %.html, \
             $(shell find docs/ -name '*.md'))
 articles := $(patsubst %.txt, %.html, \
-	$(shell find docs/ -maxdepth 2 -name '*.txt'))
+	$(shell find docs/ -maxdepth 2 -name '*.txt' | grep -Fv /gh/))
 # articles in TeX with an inappropriate var name
 texticles=$(patsubst %/, %.html, $(dir $(shell find docs/ -name 'Makefile')))
 www_root := www-root/

docs/about/githubbub.md

@@ -106,8 +106,8 @@ The original correspondence is provided here:
 [chris]: https://github.com/defunkt
 [pj]: https://github.com/pjhyett
 
-[gh-request]: /docs/gh/email-request
-[gh-request-reply]: /docs/gh/email-request-reply
-[gh-request2]: /docs/gh/email-request2
-[gh-request3]: /docs/gh/email-request3
-[gh-request3-reply]: /docs/gh/email-request3-reply
+[gh-request]: /docs/gh/email-request.txt
+[gh-request-reply]: /docs/gh/email-request-reply.txt
+[gh-request2]: /docs/gh/email-request2.txt
+[gh-request3]: /docs/gh/email-request3.txt
+[gh-request3-reply]: /docs/gh/email-request3-reply.txt