Added a NuGet.config, again temporary scaffolding
 Its adding https://staging.nuget.org where the cef.redist package temporarily lives
/CefSharp compiles with CEF3.1650. - aka CefSharp 3.31.*
Added a first version of a Nuget packages.config
This is the output from running nuget like this - I think:

    PM> Install-Package cef.redist -Pre -ProjectName CefSharp.Wpf.Example
CefSharp.props addition needed for VS2013
+ a fix to the temp NuGet.config VS2010 was yelling about
Look ma' no /CEF/**/*.dll nor /CEF/**/*.pak files!
We get them from the cef.redist NuGet now
NUGet packages.config - now depend on `cef.sdk` for CEF .lib and /include/** files
Nuke the `/CEF` folder with remaining .lib and /include files . CefSharp.Core is now NuGet powered!
More DRY with $(CefSdkDir)
Revert "More DRY with $(CefSdkDir)"

This reverts commit e25e55cdf99c3a66093b42b3d026df6cde2d47e3.
NuGet `.spec` updates for #288
NuGet `.spec` updates for #288
turns out previous commit need `x64`
- so bump `cef.sdk` in a non-DRY manner
- I also threw in a small .gitignore OCD change
I missed removing some CS.Core NuGet files
Switch `CefSharp.Core` from `solution to project Nuget packages.config
Also it's dried up now relying on `cef.sdk.props` setting $(CefSdkVer)
It requires cef.sdk NuGet version -pre2
Good enough that `CS.MinEx` want's to build ...
This is what goes into the `CefSharp.Common` and `.Wpf` Nugets version 3.31.0.pre-1
No need for CEF/ mantenance scripting here any more
Merge pull request #288 from jornh/3.31-and-native-nugets-cherrypicked-rebase

Use Chromium 31 and native NuGet packages, to avoid the massive repository bloat we've previously had. Thanks to @jornh for spending quite a massive amount of work on this one!