added static "manifesto" and 2 anchors to about.mako -> .../about/

http://centerforopenscience.org/about/ currently

* begins with the paragraph title="About the Center"
- lacks text regarding *why* to do open science

Hence I add an "open science manifesto" as described in

https://groups.google.com/forum/#!topic/openscienceframework/Wn4zslAhslc

Specifically, a short static paragraph title="Why Open Science?" above paragraph title="About the Center". I drew upon the following sources for my text (as discussed in ggroup thread above):

* first paragraph from COS project="Badges to Acknowledge Open Practices" ( https://osf.io/tvyxz/wiki/home/ )
* first paragraph from Nosek 2012 ( http://dx.doi.org/10.1177/1745691612462588 )
** ... which itself cites Braude 1979 p2. I instead link to Braude 2002 p33: same quote (search "demarcation criterion") in newer/digital (i.e., unscanned) edition in books.google

I also added 2 new anchors (each being lowercase(header) =~ s/ /-/g), one each for

* the new "manifesto" paragraph: why-open-science
* the pre-existing paragraph: about-the-center

Untested :-( but it's static HTML and I've gotta get back to "real work," so I did not setup a test environment (as described in ../requirements.txt)