Removed DLLs and update to latest versions

[Lukino2000]

Hi,

I do not know what's your thought, but I prefer don't have nuget binaries in the repository, so I deleted all the DLLs and XMLs from the bin folder, I deleted also the "packages" folder, and moved the last non-nuget dll (ImageCruncher.dll) in "libs" folder referencing from that. This way i changed .gitignore file to not include deleted content but maintaining "*.refresh" files. Visual Studio will download and use DLL from nuget and the repository remains clean.
Obviously this is just a different approach and is not strictly necessary but i prefer it.
Also take note that, this way anyone who wants to use the project must first download dependencies using visual studio or nuget.exe

I also inserted the nuget.config file into the root of the project so that the packages are placed in the correct folder (just for this project) for those people like me who prefer having "packages" folder in another location. Without this file you will see some VS errors at first compilation.

I finally updated WebMarkupMin, JQuery and Bootstrap to the latest versions, modifying the admin.js file accordingly (use of .done() in place of .success())

[madskristensen]

You can't remove the dlls since nuget restore doesn't re-add them in a website project