Fix broken links to rustc-driver.md to point to rustc-driver/intro.md

Author: thomasnyman

src/appendix/code-index.md

@@ -34,7 +34,7 @@ Item            |  Kind    | Short description           | Chapter            |
 [The HIR]: ../hir.html
 [Identifiers in the HIR]: ../hir.html#hir-id
 [The parser]: ../the-parser.html
-[The Rustc Driver and Interface]: ../rustc-driver.html
+[The Rustc Driver and Interface]: ../rustc-driver/intro.html
 [Type checking]: ../type-checking.html
 [The `ty` modules]: ../ty.html
 [Rustdoc]: ../rustdoc.html

src/memory.md

@@ -94,7 +94,7 @@ structures (e.g. the [Abstract Syntax Tree (AST)][ast], [High-Level Intermediate
 Representation (`HIR`)][hir], and the type system) and as such, arenas and
 references are heavily relied upon to minimize unnecessary memory use. This
 manifests itself in the way people can plug into the compiler (i.e. the
-[driver](./rustc-driver.md)), preferring a "push"-style API (callbacks) instead
+[driver](./rustc-driver/intro.md)), preferring a "push"-style API (callbacks) instead
 of the more Rust-ic "pull" style (think the `Iterator` trait).
 
 Thread-local storage and interning are used a lot through the compiler to reduce

src/overview.md

@@ -146,7 +146,7 @@ the final binary.
 [`Parser`]: https://doc.rust-lang.org/nightly/nightly-rustc/rustc_parse/parser/struct.Parser.html
 [`Pat`]: https://doc.rust-lang.org/beta/nightly-rustc/rustc_ast/ast/struct.Pat.html
 [`rustc_ast::ast`]: https://doc.rust-lang.org/beta/nightly-rustc/rustc_ast/index.html
-[`rustc_driver`]: rustc-driver.md
+[`rustc_driver`]: rustc-driver/intro.md
 [`rustc_interface::Config`]: https://doc.rust-lang.org/nightly/nightly-rustc/rustc_interface/interface/struct.Config.html
 [`rustc_lexer`]: https://doc.rust-lang.org/nightly/nightly-rustc/rustc_lexer/index.html
 [`rustc_parse::lexer`]: https://doc.rust-lang.org/nightly/nightly-rustc/rustc_parse/lexer/index.html
@@ -387,7 +387,7 @@ For more details on bootstrapping, see
 # References
 
 - Command line parsing
-  - Guide: [The Rustc Driver and Interface](rustc-driver.md)
+  - Guide: [The Rustc Driver and Interface](rustc-driver/intro.md)
   - Driver definition: [`rustc_driver`](https://doc.rust-lang.org/nightly/nightly-rustc/rustc_driver/)
   - Main entry point: [`rustc_session::config::build_session_options`](https://doc.rust-lang.org/nightly/nightly-rustc/rustc_session/config/fn.build_session_options.html)
 - Lexical Analysis: Lex the user program to a stream of tokens