Add C# Bindings for Chrome Network Emulation

[jakedurand]

Functionality was added to ChromeDriver in March of 2015
https://chromium.googlesource.com/chromium/src.git/+/12a55ff7369b35adb29cd28f5e3dd4ef923e3e6c

This has been added for Python and Javascript
#4011
#3624

Open PR and issue for Java
#3450
#3479

Commit for Ruby
1103cb7

I'm new here, so I apologize in advance if I did something incorrect on creating this issue! I wouldn't mind trying my hand at this myself, but I'm brand new to the Selenium project and relatively new to code in general.

[jimevans]

Fixed in commit e2bc8ea