Problems arise using gdbgui with mingw64 on Windows 10 x64

**Describe the bug**

gdbgui doesn't seem to work as expected.

**To Reproduce**

Steps to reproduce the behavior:

1. Click on 'Load Binary' to load 'output.exe' (a simple hello world c project compiled with mingw64):


The following error appears after having clicked on "Load binary":



2. Click on 'Fetch source files'. The following appears:


I can't see any reference to the source file where the main has been originally declared (e.g. Out_Converter.c)

3. Click on winnt.h source file. the following error appears:


**Expected behavior**

I would expect gdbgui to correctly load the Out_Converter.c source file to start debugging the program (output.exe).

**Please complete the following information:**
* OS: Windows 10 Pro x64
* gdbgui version (`gdbgui -v`): 0.13.1.1
* gdb version (`gdb -v`): GNU gdb (GDB) 8.2
* browser [e.g. chrome, safari]: Chrome x64 v72.0.3626.81
* python packages (`pip freeze`):

intelhex==2.2.1
numpy==1.15.2
Pygments==2.3.1

* Python version (`python -v`): 2.7.15

**Additional context**

Add any other context about the problem here.

mingw64 is currently installed into C:\msys64:


I'm running gdbgui_0.13.1.1.exe with no arguments.

'Out_Converter.c' is placed into its project folder.