blog: Make the atom feed title configurable.
blog: Make the atom feed title configurable.

The blog code is quite generic and with the replacement of template and
static files, it can be re-used. But the atom feed title is hard-coded
into the code. This patch adds a field to set the atom feed title to
the Config structure and uses it in the code where the title was
previously hard-coded.

A CL sent separately will set this Config field in the main package in
the go.blog sub-repository. (See CL 16850043 for that other patch).

R=golang-dev, adg
CC=golang-dev
https://golang.org/cl/16830043

jdhenke/tools,golang/tools,magiccao/tools,argandas/tools,springning/tools,dmitris/tools,sshetty10/tools,jdhenke/tools,josharian/tools,matryer/tools,springning/tools,maddyonline/tools,syreclabs/go-tools,springning/tools,matryer/tools,runcom/tools,cmars/tools,glasser/golang-tools,maddyonline/tools,cmars/tools,syreclabs/go-tools,magiccao/tools,runcom/tools,cw2018/tools,runcom/tools,josharian/tools,maddyonline/tools,golang/tools,maddyonline/tools,4ad/tools,matryer/tools,cw2018/tools,4ad/tools,argandas/tools,cmars/tools,cw2018/tools,dmitris/tools,dmitris/tools,golang/tools,josharian/tools,cw2018/tools,sshetty10/tools,golang/tools,runcom/tools,nicot/tools,nicot/tools,syreclabs/go-tools,glasser/golang-tools,4ad/tools,syreclabs/go-tools,jdhenke/tools,jdhenke/tools,josharian/tools,glasser/golang-tools,magiccao/tools,nicot/tools,sshetty10/tools,magiccao/tools,nicot/tools,cmars/tools,argandas/tools,matryer/tools,springning/tools,argandas/tools,syreclabs/go-tools,dmitris/tools,syreclabs/go-tools,glasser/golang-tools,golang/tools,sshetty10/tools