Implement generic methods on arrays

[jp2masa]

Currently we don't handle generic methods on arrays.
Example:

IEnumerable<string> xEnumerable;
string[] xArray = new string[] { "a", "b", "c" };
xEnumerable = xArray;
xEnumerable.GetEnumerator();

This code won't work, because Array doesn't have an implementation for this method. Array can be used as ICollection<T>, IEnumerable<T> and IList<T>
The implementations for these interfaces are in System.SZArrayHelper, but the compiler needs an implementation that replaces calls to the generic method on arrays with calls to the methods in SZArrayHelper.

[jp2masa]

This issue was moved to CosmosOS/IL2CPU#15