Tells PyPi that desc is MD and removed C++ fs usage

Looks like gcc8 shipped with manylinux2014 container doesn't support
filesystem module.

Signed-off-by: Alexis Jeandet <alexis.jeandet@member.fsf.org>

include/cdf-io/cdf-io.hpp

@@ -30,7 +30,6 @@
 #include "cdf-io-variable.hpp"
 #include "cdf-io-zlib.hpp"
 #include <algorithm>
-#include <filesystem>
 #include <fstream>
 #include <iostream>
 #include <numeric>
@@ -140,9 +139,10 @@ namespace
 
 std::optional<CDF> load(const std::string& path)
 {
-    if (std::filesystem::exists(path))
+    auto fs = std::fstream { path, std::ios::in | std::ios::binary };
+    if (fs.is_open())
     {
-        buffers::stream_adapter buffer { std::fstream { path, std::ios::in | std::ios::binary } };
+        buffers::stream_adapter buffer { std::move(fs) };
         return impl_load(buffer);
     }
     return std::nullopt;

meson.build

@@ -1,7 +1,7 @@
 project(
   'cdfpp',
   'cpp',
-  version : '0.1.0',
+  version : '0.1.3',
   default_options : ['warning_level=3', 'cpp_std=c++17'],
   license : 'GPL3'
 )

setup.py

@@ -5,7 +5,7 @@
 
 setup(
     name="pycdfpp",
-    version="0.1.2",
+    version="0.1.3",
     description="A modern C++ header only cdf library",
     author='Alexis Jeandet',
     author_email='alexis.jeandet@member.fsf.org',
@@ -22,6 +22,7 @@
         ],
     license="GNU General Public License v3",
     long_description=readme,
+    long_description_content_type='text/markdown',
     keywords='CDF NASA Space Physics Plasma',
     url='https://github.com/SciQLop/CDFpp',
     packages=['pycdfpp']