Subtree memorization / reactive templates (#488)

This commit adds subtree memoization to Dioxus.

Subtree memoization is basically a compile-time step that drastically 
reduces the amount of work the diffing engine needs to do at runtime by
extracting non-changing nodes out into a static "template." Templates 
are then understood by the various renderers in the ecosystem as a 
faster way of rendering the same items. 

For example, in the web, templates are simply a set of DOM Nodes created 
once and then cloned later. This is the same pattern frameworks like Lithtml
and SolidJS use to achieve near-perfect performance. 

Subtree memoization adds an additional level of complexity to Dioxus. The RSX
macro needs to be much smarter to identify changing/nonchanging nodes and
generate a mapping between the Template and its runtime counterparts.

This commit represents a working starter point for this work, adding support 
for templates for the web, desktop, liveview, ssr, and native-core renderers.
In the future we will try to shrink code generation, generally improve 
performance, and simplify our implementation.

packages/dioxus/Cargo.toml

@@ -17,12 +17,6 @@ dioxus-html = { path = "../html", version = "^0.2.1", optional = true }
 dioxus-core-macro = { path = "../core-macro", version = "^0.2.1", optional = true }
 dioxus-hooks = { path = "../hooks", version = "^0.2.1", optional = true }
 dioxus-rsx = { path = "../rsx", optional = true }
-dioxus-rsx-interpreter = { path = "../rsx_interpreter", optional = true }
-
-
-# dioxus-interpreter-js = { path = "./packages/interpreter", version = "^0.2.1", optional = true }
-# dioxus-native-core = { path = "./packages/native-core", version = "^0.2.0", optional = true }
-# dioxus-native-core-macro = { path = "./packages/native-core-macro", version = "^0.2.0", optional = true }
 
 [features]
 default = ["macro", "hooks", "html"]
@@ -30,8 +24,7 @@ macro = ["dioxus-core-macro", "dioxus-rsx"]
 html = ["dioxus-html"]
 hooks = ["dioxus-hooks"]
 hot-reload = [
-    "dioxus-core-macro/hot-reload",
-    "dioxus-rsx-interpreter",
+    "dioxus-core/hot-reload",
 ]
 
 [dev-dependencies]