Updated URLs in docs

[Matthew Davis]

Looking at the help files, I noticed the URLs for the rrd
documentation has been changed.

from www/html/howtograph.html
http://people.ee.ethz.ch/~oetiker/webtools/rrdtool/doc/rrdcreate.en.html
is now
http://oss.oetiker.ch/rrdtool/doc/rrdcreate.en.html

http://people.ee.ethz.ch/~oetiker/webtools/rrdtool/doc/rrdgraph.en.html
is now
http://oss.oetiker.ch/rrdtool/doc/rrdgraph.en.html

And

from www/html/install.html
http://people.ee.ethz.ch/~oetiker/webtools/rrdtool/
is now
http://oss.oetiker.ch/rrdtool/

-- 
Matthew Davis
http://familycampground.org/matthew/