Renamed Functions to Methods

Microsoft refers to member functions as methods in their
standard documentation http://msdn.microsoft.com/en-us/library/ms173114.aspx

Capitalized all method names:
The C# standard uses a Pascal-Case (Camel-Case starting with a capital)
for all Classes and Methods
Switched Functions to Methods in Welcome.md
Merge pull request #112 from liam-middlebrook/master

Functions are Methods in C#