README: Autogenerate from library documentation using cargo-readme

Based on the suggestion from @katyo in [1] and implementation in [2].

[1]: Smithay#9 (comment)
[2]: https://github.com/katyo/aubio-rs/pull/18/files

.github/workflows/ci.yml

@@ -36,6 +36,7 @@ jobs:
 
   doc:
     runs-on: ubuntu-latest
+    needs: cargo-readme
     steps:
       - uses: actions/checkout@v2
       - name: Setup Rust
@@ -59,6 +60,15 @@ jobs:
           DOCS_RS: 1
         with:
           command: doc
+      - name: Setup Cargo readme
+        uses: actions/cache@v2
+        with:
+          path: ~/.cargo/bin/cargo-readme
+          key: ${{ runner.os }}-cargo-readme
+      - name: Check if README.md is up-to-date
+        run: |
+          cargo readme > README.md
+          git diff --quiet || (echo '::error::Generated README is different, please regenerate with `cargo readme > README.md`'; git diff; false)
 
   check:
     runs-on: ubuntu-latest
@@ -305,3 +315,19 @@ jobs:
           registry-token: ${{ secrets.CRATES_TOKEN }}
           args: --no-verify
           #dry-run: true
+
+  cargo-readme:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Prepare cache
+        uses: actions/cache@v2
+        id: cache
+        with:
+          path: ~/.cargo/bin/cargo-readme
+          key: ${{ runner.os }}-cargo-readme
+      - name: Install cargo readme
+        if: steps.cache.outputs.cache-hit != 'true'
+        uses: actions-rs/cargo@v1
+        with:
+          command: install
+          args: cargo-readme

README.md

@@ -1,3 +1,20 @@
+gbm
+=
+
+[![Actions Status](https://github.com/Smithay/gbm.rs/workflows/Continuous%20integration/badge.svg)](https://github.com/Smithay/gbm.rs/actions)
+[![Latest version](https://img.shields.io/crates/v/hassle-rs.svg)](https://crates.io/crates/hassle-rs)
+[![Documentation](https://docs.rs/hassle-rs/badge.svg)](https://docs.rs/hassle-rs)
+[![Lines of code](https://tokei.rs/b1/github/Smithay/gbm.rs)](https://github.com/Smithay/gbm.rs)
+![MIT](https://img.shields.io/badge/license-MIT-blue.svg)
+
+### Usage
+
+Add to your `Cargo.toml`:
+
+```toml
+gbm = "0.7.0"
+```
+
 ## Safe `libgbm` bindings for [rust](https://www.rust-lang.org)
 
 The Generic Buffer Manager
@@ -11,30 +28,23 @@ the underlying memory manager.
 This library is best used in combination with [`drm-rs`](https://github.com/Smithay/drm-rs),
 provided through the `drm-support` feature.
 
-## Usage
-
-Add to your Cargo.toml
-
-```toml
-gbm = "0.7.0"
-```
-
-## Example
+### Example
 
 ```rust
-extern crate drm;
-extern crate gbm;
-
 use drm::control::{self, crtc, framebuffer};
 use gbm::{BufferObjectFlags, Device, Format};
 
+#
+#
+#
+#
 // ... init your drm device ...
 let drm = init_drm_device();
 
 // init a GBM device
 let gbm = Device::new(drm).unwrap();
 
-// create a buffer
+// create a 4x4 buffer
 let mut bo = gbm
     .create_buffer_object::<()>(
         1280,
@@ -59,7 +69,10 @@ bo.write(&buffer).unwrap();
 // create a framebuffer from our buffer
 let fb = gbm.add_framebuffer(&bo, 32, 32).unwrap();
 
+#
 // display it (and get a crtc, mode and connector before)
 gbm.set_crtc(crtc_handle, Some(fb), (0, 0), &[con], Some(mode))
     .unwrap();
 ```
+
+License: MIT

README.tpl

@@ -0,0 +1,20 @@
+{{crate}}
+=
+
+[![Actions Status](https://github.com/Smithay/gbm.rs/workflows/Continuous%20integration/badge.svg)](https://github.com/Smithay/gbm.rs/actions)
+[![Latest version](https://img.shields.io/crates/v/hassle-rs.svg)](https://crates.io/crates/hassle-rs)
+[![Documentation](https://docs.rs/hassle-rs/badge.svg)](https://docs.rs/hassle-rs)
+[![Lines of code](https://tokei.rs/b1/github/Smithay/gbm.rs)](https://github.com/Smithay/gbm.rs)
+![MIT](https://img.shields.io/badge/license-MIT-blue.svg)
+
+### Usage
+
+Add to your `Cargo.toml`:
+
+```toml
+gbm = "{{version}}"
+```
+
+{{readme}}
+
+License: {{license}}

src/lib.rs

@@ -60,6 +60,7 @@
 //!         BufferObjectFlags::SCANOUT | BufferObjectFlags::WRITE,
 //!     )
 //!     .unwrap();
+//!
 //! // write something to it (usually use import or egl rendering instead)
 //! let buffer = {
 //!     let mut buffer = Vec::new();