Add compilation of minimal hello world example to CI

This prevents issue #3 from re-occurring.

.github/workflows/build_and_test.yml

@@ -1,40 +1,48 @@
-name: Build and run tests
-
-on:
-  # Trigger the workflow on push or pull request,
-  # but only for the master branch
-  push:
-    branches:
-      - master
-  pull_request:
-    branches:
-      - master
-
-jobs:
-  ubuntu:
-
-    name: Test on Ubuntu
-    runs-on: ubuntu-latest
-
-    steps:
-    - uses: actions/checkout@v2
-
-    - name: Update Rust
-      run: rustup update
-
-    - name: Run tests
-      run: cargo test --all-targets
-
-  windows:
-
-    name: Test on Windows
-    runs-on: windows-latest
-
-    steps:
-      - uses: actions/checkout@v2
-      - name: Run tests
-        run: |
-          call "C:\Program Files (x86)\Microsoft Visual Studio\2019\Enterprise\VC\Auxiliary\Build\vcvars64.bat"
-          cargo test --all-targets
-        shell: cmd
-
+name: Build and run tests
+
+on:
+  # Trigger the workflow on push or pull request,
+  # but only for the master branch
+  push:
+    branches:
+      - master
+  pull_request:
+    branches:
+      - master
+
+jobs:
+  ubuntu:
+
+    name: Test on Ubuntu
+    runs-on: ubuntu-latest
+
+    steps:
+    - uses: actions/checkout@v2
+
+    - name: Update Rust
+      run: rustup update
+
+    - name: Run tests
+      run: cargo test --all-targets
+
+    - name: Build matrixcompare-minimal
+      run: cargo build --manifest-path=matrixcompare-minimal/Cargo.toml
+
+  windows:
+
+    name: Test on Windows
+    runs-on: windows-latest
+
+    steps:
+      - uses: actions/checkout@v2
+      - name: Run tests
+        run: |
+          call "C:\Program Files (x86)\Microsoft Visual Studio\2019\Enterprise\VC\Auxiliary\Build\vcvars64.bat"
+          cargo test --all-targets
+        shell: cmd
+
+      - name: Build matrixcompare-minimal
+        run: |
+          call "C:\Program Files (x86)\Microsoft Visual Studio\2019\Enterprise\VC\Auxiliary\Build\vcvars64.bat"
+          cargo build --manifest-path=matrixcompare-minimal/Cargo.toml
+        shell: cmd

matrixcompare-minimal/Cargo.toml

@@ -0,0 +1,8 @@
+# See comment in src/main.rs for the purpose of this crate
+[package]
+name = "matrixcompare-minimal"
+version = "0.1.0"
+edition = "2018"
+
+[dependencies]
+matrixcompare = { version = "0.1.4", path = ".." }

matrixcompare-minimal/src/main.rs

@@ -0,0 +1,8 @@
+//! This "minimal" crate is just a means of testing in CI that the most barebones
+//! example involving `matrixcompare` compiles. This is intended to prevent an issue like
+//! that reported in [issue #3](https://github.com/Andlon/matrixcompare/issues/3) from
+//! happening again.
+
+fn main() {
+    println!("Hello, world!");
+}