Rename function Symbol with LSP

[kobyhallx]

User should be able to rename symbol they work with, function name which leads to renaming all of the references across project.

Consider following:

File: baz.nr

1: pub fn foo() {}

File: main.nr

01: mod baz;
02: 
03: use baz::foo;
04: 
05: fn bar() {
06:     foo();
07: }
08: 
09: fn main() {
10:     foo();
11: } 

Choosing rename foo on line 10, should rename symbol on line 10, 06, 03 (import) and 1 on file baz.nr