Add LinkedList::remove()
Add LinkedList::remove()

LinkedList::remove() removes the element at the specified index and returns it.

Signed-off-by: Bijan Tabatabai <5faaef3c16062c48dd4e0542be6fd8403d09b4a2@yahoo.com>

aidancully/rust,graydon/rust,aidancully/rust,aidancully/rust,aidancully/rust,aidancully/rust,graydon/rust,graydon/rust,graydon/rust,aidancully/rust,graydon/rust,graydon/rust