Add Experimental Content-Security-Policy-Support (CSP) for Fauxton

Like every web application, Fauxton is vulnerable against XSS and
CSP is a technology that tries to help against that.

The patch makes it possible to enable CSP for the /_utils path and
allows configuration of the sent header.

The default setting for the value of the header breaks the old
Futon, when CSP is enabled there. The old Futon has alot of
inline-JavaScript which is not allowed in the setting I have
chosen as default.

For development, the header is also sent from the Node server
which launches Fauxton in dev-mode.

People can enable the feature by setting enable = true in the
section [csp] of their configs
Fauxton: Fix show me api link

 * use data-bypass attribute to circumvent backbone routing
Fauxton: Fix font awesome url to work for release
Fauxton: Content Security Policy optional for dev

This just makes the content security policy optional for
development.
fix attachment view to bypass
Fauxton: Create fx roles

Fauxton auth works by checking what roles a user has and then decide if
they have access to a specific route. The only problem is a regular user
might get created but not have any roles. Unlike an admin user who get
assigned all the roles on creation.

The idea behind this is that certain routes should require a user to be
logged in but not necessary have any roles eg. #changePassword route.

This allows for a standard fauxton role that all logged in users get given so that
we can check via the roles if they are logged
Fauxton: Fix clone cancel button

This fixes the issue that when a user cancels a clone doc it goes back
to all docs. Now it just closes the modal.
Fauxton: updated dev dependancies
Fix missing stale query option
Fauxton: Add view filter

This allows a module to register an extension to filter out what views
should be displayed in the side bar.
An example of usage is to only display views that have
"language:javascript"
Fauxton: Remove settings.json.dev

We don't use this file and its causing confusion with new contributors.
The grunt task look for a `settings.json`, if it doesn't find that it
defaults to settings.json.default
Fauxton: Upgrade node-http-proxy

Some modifications have to be made because the API changed when
the module reached v1.0
Fauxton: fix build
remove whitespace
remove unused configuration for resizable container
Fauxton: fix scrollbar-issue - COUCHDB-2234

- Try to honor borders in calculating the width
- Adjust magic numbers to new widths of the left area
- Refactor the header/api-url section
- Removing the maximum widths of 1400px and 1500px, which caused
  vertical scrollbars to appear at 1400px (which is on top of the
  page content, some hundred pixels away from the left side on
  large screens) on a system like windows

COUCHDB-2234
Fauxton: verifyinstall fix for PouchDB Server

Closes COUCHDB-2266
Add modified .gitignore from couchdb
modify the documentation for the installation
Fauxton: Fix scrollbar from sidebar on collapsed state in Chrome

With a collapsed sidebar, in Chrome, the scrollbar was always
visible, even if the z-index of the dashboard was higher.