Auto merge of #322 - DarkEld3r:316-add-categories-to-cargo-toml, r=SimonSapin

Add categories to Cargo.toml

Fixes #316

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Cargo.toml

@@ -9,6 +9,7 @@ documentation = "https://docs.rs/url"
 repository = "https://github.com/servo/rust-url"
 readme = "README.md"
 keywords = ["url", "parser"]
+categories = ["parser-implementations", "web-programming", "encoding"]
 license = "MIT/Apache-2.0"
 
 [workspace]