Migrate to github actions for CI

Author: alexcrichton

.github/workflows/main.yml

@@ -0,0 +1,50 @@
+name: CI
+on: [push, pull_request]
+
+jobs:
+  test:
+    name: Test
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        rust: [stable, beta, nightly]
+    steps:
+    - uses: actions/checkout@master
+    - name: Install Rust (
+      run: rustup update ${{ matrix.rust }} && rustup default ${{ matrix.rust }}
+    - run: cargo test
+    - run: cargo test --features debug
+    - run: cargo test --features global
+    - run: cargo test --release
+    - run: cargo test --features debug --release
+    - run: RUSTFLAGS='--cfg test_lots' cargo test --release
+    - run: RUSTFLAGS='--cfg test_lots' cargo test --release --features debug
+
+  rustfmt:
+    name: Rustfmt
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@master
+    - name: Install Rust
+      run: rustup update stable && rustup default stable && rustup component add rustfmt
+    - run: cargo fmt -- --check
+
+  wasm:
+    name: WebAssembly
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@master
+    - name: Install Rust
+      run: rustup update stable && rustup default stable && rustup target add wasm32-unknown-unknown
+    - run: cargo build --target wasm32-unknown-unknown
+    - run: cargo build --target wasm32-unknown-unknown --release
+
+  alloc_api:
+    name: Allocator API
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@master
+    - name: Install Rust
+      run: rustup update nightly && rustup default nightly
+    - run: cargo test --features 'allocator-api global'
+

.travis.yml

@@ -2,8 +2,6 @@
 
 A port of [dlmalloc] to Rust.
 
-[![Build Status](https://travis-ci.com/alexcrichton/dlmalloc-rs.svg?branch=master)](https://travis-ci.com/alexcrichton/dlmalloc-rs)
-
 [Documentation](https://docs.rs/dlmalloc)
 
 [dlmalloc]: http://g.oswego.edu/dl/html/malloc.html