external: update backward-cpp to v1.4

rename the directory name to backward-cpp

Closes: #803
Signed-off-by: Shengjing Zhu <i@zhsj.me>

external/backward-cpp/conanfile.py

@@ -0,0 +1,45 @@
+from conans import ConanFile, CMake
+import os
+
+class BackwardCpp(ConanFile):
+    settings = 'os', 'compiler', 'build_type', 'arch'
+    name = 'backward'
+    url = 'https://github.com/bombela/backward-cpp'
+    license = 'MIT'
+    version = '1.3.0'
+    options = {
+        'stack_walking_unwind': [True, False],
+        'stack_walking_backtrace': [True, False],
+        'stack_details_auto_detect': [True, False],
+        'stack_details_backtrace_symbol': [True, False],
+        'stack_details_dw': [True, False],
+        'stack_details_bfd': [True, False],
+        'shared': [True, False]
+    }
+    default_options = (
+        'stack_walking_unwind=True',
+        'stack_walking_backtrace=False',
+        'stack_details_auto_detect=True',
+        'stack_details_backtrace_symbol=False',
+        'stack_details_dw=False',
+        'stack_details_bfd=False',
+        'shared=False'
+    )
+    exports = 'backward.cpp', 'backward.hpp', 'test/*', 'CMakeLists.txt', 'BackwardConfig.cmake'
+    generators = 'cmake'
+
+    def build(self):
+        cmake = CMake(self)
+
+        cmake.configure(defs={'BACKWARD_' + name.upper(): value for name, value in self.options.values.as_list()})
+        cmake.build()
+
+    def package(self):
+        self.copy('backward.hpp', os.path.join('include', 'backward'))
+        self.copy('*.a', dst='lib')
+        self.copy('*.so', dst='lib')
+        self.copy('*.lib', dst='lib')
+        self.copy('*.dll', dst='lib')
+
+    def package_info(self):
+        self.cpp_info.libs = ['backward']