Added image TeapotIn3Dviewport.png for Wiki

Working on the getting started Wiki, can't link to an image unless its
in the repository.
Added name and email to contributors

Updated contributors list with name and email
Merge pull request #3 from helix-toolkit/master

Merge pull request #80 from johnsonlu/master
Do not raise ModelsSelectedByRectangleEventArgs when the rectangle is zero.
Can use point to clear existing selection.
Merge pull request #81 from dgwaldo/master

Added .png file to images for getting started wiki
Merge pull request #84 from johnsonlu/master

Do not raise ModelsSelectionByRectangleEventArgs when the size of rectangle is zero
Added simple STL exporter
Fixing failing build.

Some public/protected methods did not have documentation and the
StlExporter.cs was not included for compilation in the NET40 project.
Merge pull request #87 from vidstige/stl_exporter

Added simple STL exporter
wrong path to ExampleBrowser_NET40 project fixed

the WPF subfolder was missing in the path
Merge pull request #91 from chrkon/master

wrong path to ExampleBrowser_NET40 project fixed
Merge remote-tracking branch 'upstream/master'
Add text and point rendering files to 4.5 project.