Windows: Clean up build instructions

win/README.md

 # Windows Installer
 
-We use [msys2](http://www.msys2.org/) for creating the Windows installer
+We use [msys2](https://www.msys2.org/) for creating the Windows installer
 and development on Windows.
 
 
-### Development
------------
+## Development
 
-Download [msys2](http://www.msys2.org/) (msys2-x86_64-xxx.exe) and follow the install instructions on the [msys2](http://www.msys2.org/) startpage (**Important!**)
+Download [msys2](https://www.msys2.org/) (msys2-x86_64-xxx.exe) and follow the install instructions on the [msys2](https://www.msys2.org/) startpage (**Important!**)
 
 * Fork the master branch on dev.gajim.org
-* Execute ``C:\msys64\msys2_shell.cmd -mingw64``
-* Run ``pacman -S git`` to install git
-* Run ``git clone https://dev.gajim.org/USERNAME/gajim.git``
-* Run ``cd gajim/win`` to end up where this README exists.
-* Execute ``./dev_env.sh`` to install all the needed dependencies.
-* Now go to the git root dir ``cd ..``
-* Launch Gajim ``./launch.py``
+* Execute `C:\msys64\msys2_shell.cmd -mingw64`
+* Run `pacman -S git` to install git
+* Run `git clone https://dev.gajim.org/USERNAME/gajim.git`
+* Run `cd gajim/win` to end up where this README exists.
+* Execute `./dev_env.sh` to install all the needed dependencies.
+* Now go to the git root dir `cd ..`
+* Launch Gajim `./launch.py`
 
 
-### Build Gajim / Creating an Installer
----------------------
+## Build Gajim / Create an Installer
 
 Follow the steps in the Development section, but instead of `./dev_env.sh` execute `./build.sh i686` or `./build.sh x86_64`.