Update Conan recipe

- Apply new conventions introduced on Conan 1.8
- Removed outdated settings
- Update license to follow SPDX format

Closes #926
Closes #943

.conan/test_package/CMakeLists.txt

@@ -0,0 +1,11 @@
+cmake_minimum_required(VERSION 3.2.0)
+project(test_package CXX)
+
+include(${CMAKE_BINARY_DIR}/conanbuildinfo.cmake)
+conan_basic_setup(TARGETS)
+
+find_package(Catch2 REQUIRED CONFIG)
+
+add_executable(${PROJECT_NAME} test_package.cpp)
+target_link_libraries(${PROJECT_NAME} CONAN_PKG::Catch2)
+set_target_properties(${PROJECT_NAME} PROPERTIES CXX_STANDARD 11)

.conan/test_package/conanfile.py

@@ -0,0 +1,19 @@
+#!/usr/bin/env python
+# -*- coding: utf-8 -*-
+from conans import ConanFile, CMake
+import os
+
+
+class TestPackageConan(ConanFile):
+    settings = "os", "compiler", "build_type", "arch"
+    generators = "cmake"
+
+    def build(self):
+        cmake = CMake(self)
+        cmake.configure()
+        cmake.build()
+
+    def test(self):
+        assert os.path.isfile(os.path.join(self.deps_cpp_info["Catch2"].rootpath, "licenses", "LICENSE.txt"))
+        bin_path = os.path.join("bin", "test_package")
+        self.run("%s -s" % bin_path, run_environment=True)

.conan/test_package/test_package.cpp

@@ -0,0 +1,15 @@
+#define CATCH_CONFIG_MAIN
+
+#include <catch2/catch.hpp>
+
+int Factorial( int number ) {
+    return number <= 1 ? 1 : Factorial( number - 1 ) * number;
+}
+
+TEST_CASE( "Factorial Tests", "[single-file]" ) {
+    REQUIRE( Factorial(0) == 1 );
+    REQUIRE( Factorial(1) == 1 );
+    REQUIRE( Factorial(2) == 2 );
+    REQUIRE( Factorial(3) == 6 );
+    REQUIRE( Factorial(10) == 3628800 );
+}