Add new base object stuff, gc dependency

I'm not writing my own GC, it's a huge pain in Rust. I'm using the gc
library instead.

Base object stuff implementation is here too. Hopefully going to start
using ObjPtr instead of Value next.

Signed-off-by: Alek Ratzloff <alekratz@gmail.com>

Cargo.lock

@@ -52,6 +52,27 @@ dependencies = [
  "vec_map",
 ]
 
+[[package]]
+name = "gc"
+version = "0.4.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "3edaac0f5832202ebc99520cb77c932248010c4645d20be1dc62d6579f5b3752"
+dependencies = [
+ "gc_derive",
+]
+
+[[package]]
+name = "gc_derive"
+version = "0.4.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "60df8444f094ff7885631d80e78eb7d88c3c2361a98daaabb06256e4500db941"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn",
+ "synstructure",
+]
+
 [[package]]
 name = "heck"
 version = "0.3.3"
@@ -181,6 +202,7 @@ dependencies = [
 name = "sybil"
 version = "0.1.0"
 dependencies = [
+ "gc",
  "lazy_static",
  "regex",
  "structopt",
@@ -198,6 +220,18 @@ dependencies = [
  "unicode-xid",
 ]
 
+[[package]]
+name = "synstructure"
+version = "0.12.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f36bdaa60a83aca3921b5259d5400cbf5e90fc51931376a9bd4a0eb79aa7210f"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn",
+ "unicode-xid",
+]
+
 [[package]]
 name = "textwrap"
 version = "0.11.0"