[glade] Readme.md: cleanup

[Juan Pablo Ugarte <jpu src gnome org>]

commit c94cdbe19c2dd2b072e09de3e9aee991aca3f9b2
Author: Juan Pablo Ugarte <juanpablougarte gmail com>
Date:   Wed Aug 26 19:55:24 2020 -0300

    Readme.md: cleanup
    
    Add manual installation, Linux, Windows and OSX instructions

 README.md | 110 ++++++++++++++++++++++++++++++++++++++++++++++++--------------
 1 file changed, 86 insertions(+), 24 deletions(-)
---
diff --git a/README.md b/README.md
index dbc3b1cc..e3ee9db9 100644
--- a/README.md
+++ b/README.md
@@ -1,17 +1,15 @@
 # Glade
 
-A user interface designer for Gtk+ and GNOME
+User interface designer for Gtk+ and GNOME
 
-Web: <http://glade.gnome.org>
+* Web - <https://glade.gnome.org>
+* Git - <https://gitlab.gnome.org/GNOME/glade>
 
 Mailing Lists: 
 
-* <glade-users-list gnome org>
-  * For discussions about using Glade to build applications.
-* <glade-devel-list gnome org>
-  * For discussions about the development of Glade itself.
+* <glade-users-list gnome org> - About using Glade to build applications.
+* <glade-devel-list gnome org> - About the development of Glade itself.
 
-<a href='https://flathub.org/apps/details/org.gnome.Glade'><img width='240' alt='Download on Flathub' 
src='https://flathub.org/assets/badges/flathub-badge-i-en.png'/></a>
 
 ## General Information
 
@@ -25,29 +23,93 @@ define a new GtkWidget derived object class using Gtk+ new template feature.
 By using GtkBuilder, Glade XML files can be used in numerous programming 
 languages including C, C++, C#, Vala, Java, Perl, Python, and others. 
 
-## About Glade
 
-This version of Glade (Glade >= 3.10) targets GTK+ >= 3.0 and is parallel
-installable with Glade 3.8.
-
-If you need to work with Glade projects that target GTK+2, you need an
-installation of Glade 3.8 (more information on http://blogs.gnome.org/tvb/2011/01/15/the-glade-dl/)
+This version of Glade targets GTK 3  
+If you need to work with GTK 2, you can still use Glade 3.8
+([more information](http://blogs.gnome.org/tvb/2011/01/15/the-glade-dl/))
 
 ## License
 
-Glade is distributed under the GNU General Public License (GPL), as described
-in the COPYING file.
+Glade is distributed under the
+[GNU General Public License](https://www.gnu.org/licenses/gpl-2.0.en.html),
+version 2 (GPL) and
+[GNU Library General Public License](https://www.gnu.org/licenses/old-licenses/lgpl-2.0.en.html),
+version 2 (LGPL) as described in the COPYING file.
+
+## Manual instalation
+
+Requirements
+
+* C compiler like [gcc](https://gcc.gnu.org/)
+* [Meson](http://mesonbuild.org) build system
+* [GTK](http://www.gtk.org) 3.24.0 or above
+* [libxml](http://xmlsoft.org/) 2.4.1 - used to parse XML files
+* libgirepository1.0 - Build-time dependency
+* xsltproc - for man pages generation
+
+Optional dependencies:
+
+* libwebkit2gtk-4.0 - For Webkit plugin
+* python-gi - For Python plugin
+* libgjs - For JavaScript plugin
+
+Download sources from git and build using meson/ninja
+
+       # Install dependencies, for example in debian
+       sudo apt install gcc meson libgtk-3-dev libxml2-dev libgirepository1.0-dev xsltproc 
+       
+       # Optional dependencies
+       sudo apt install libgjs-dev libwebkit2gtk-4.0-dev python-gi-dev
+
+       # Clone the source repository or download tarball
+       git clone https://gitlab.gnome.org/GNOME/glade.git
+
+       # Create build directory and configure project
+       mkdir glade/build && cd glade/build
+       meson --prefix=~/.local
+
+       # Build and install
+       ninja
+       ninja install
+
+To run it you might need to set up LD_LIBRARY_PATH depending on your
+distribution defaults
+
+       LD_LIBRARY_PATH=~/.local/lib/x86_64-linux-gnu/ glade
+
+## Linux
+
+Debian
+
+       apt install glade
+
+Fedora
+
+       yum install glade
+
+Any distribution with Flatpak
+
+       flatpak install flathub org.gnome.Glade
+
+[<img width='240' alt='Download on Flathub' 
src='https://flathub.org/assets/badges/flathub-badge-i-en.png'/>](https://flathub.org/apps/details/org.gnome.Glade)
+
+## Windows
+
+Available as a
+[package](https://packages.msys2.org/package/mingw-w64-x86_64-glade) in
+[MSYS2](https://www.msys2.org/)
+
+       pacman -S mingw-w64-x86_64-glade
+
+## OSX
+
+Available as a [package](https://formulae.brew.sh/formula/glade) in
+[Brew](https://brew.sh/)
+
+       brew install glade
+
 
-## Requirements
 
-* GTK+ 3.24.0 or above - <http://www.gtk.org>  
-  You also need the glib, pango and atk libraries.
-  Make sure you have the devel packages as well, as these will contain the
-  header files which you will need to compile C applications.
 
-* libxml 2.4.1 - used to parse the XML files. If you have GNOME 2 you
-  should already have this.
 
-## Installation
 
-See the file '[INSTALL](INSTALL)'