docs: Update install instructions

README.md

@@ -1,6 +1,6 @@
 # defenestrate
 
-> **Source Code Spelling Correction**
+> **Throw spelling errors out the window**
 
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@@ -10,11 +10,10 @@
 
 ## Install
 
-Add to your `Cargo.toml`:
+For now, `rust` is required for install:
 
 ```toml
-[dependencies]
-defenestrate = "0.3"
+cargo install defenestrate
 ```
 
 ## License