WIP commit:

* Fix up project structures
* combine vars and funcs table
* make a place for old code that may be useful to reference
* singleton pattern for sym table

Commentary:
When this change is finally finished I promise to use feature branches
from here on out

the_rewrite/tests/test_vars.rs

@@ -1,64 +0,0 @@
-mod var_lib_tests {
-    use relish::ast::{eval, lex, Ctr, FTable, VTable};
-    use relish::stdlib::get_stdlib;
-    use std::cell::RefCell;
-    use std::rc::Rc;
-
-    #[test]
-    fn test_variable_export_and_lookup() {
-        let doc1 = "(export test 1)";
-        let doc2 = "(concat test)";
-        let result = "1";
-        let vt = Rc::new(RefCell::new(VTable::new()));
-        let ft: Rc<RefCell<FTable>>;
-        match get_stdlib(vt.clone()) {
-            Ok(f) => ft = f,
-            Err(s) => {
-                ft = Rc::new(RefCell::new(FTable::new()));
-                println!("Couldnt get stdlib: {}!", s);
-                assert!(false);
-            }
-        }
-
-        match lex(doc1.to_string()) {
-            Err(s) => {
-                println!("Couldnt lex {}: {}", doc1, s);
-                assert!(false);
-            }
-
-            Ok(tree) => match eval(tree, vt.clone(), ft.clone(), false) {
-                Err(s) => {
-                    println!("Couldnt eval {}: {}", doc2, s);
-                    assert!(false);
-                }
-
-                Ok(ctr) => {
-                    println!("{:#?}", vt);
-                    match ctr {
-                        Ctr::None => assert!(true),
-                        _ => assert!(false),
-                    }
-                }
-            },
-        }
-
-        match lex(doc2.to_string()) {
-            Err(s) => {
-                println!("Couldnt lex {}: {}", doc2, s);
-                assert!(false);
-            }
-
-            Ok(tree) => match eval(tree, vt.clone(), ft.clone(), false) {
-                Err(s) => {
-                    println!("Couldnt eval {}: {}", doc2, s);
-                    assert!(false);
-                }
-
-                Ok(ctr) => match ctr {
-                    Ctr::String(s) => assert_eq!(s, result),
-                    _ => assert!(false),
-                },
-            },
-        }
-    }
-}