message: Update README.md
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diff: How to compile RINGMesh {#ringmesh_compiling}
  =======================
  -[![Build status](https://ci.appveyor.com/api/projects/status/d2hkhxnlb4ke6gy0/branch/default?svg=true)](https://ci.appveyor.com/project/ArnaudBotella/ringmesh/branch/default)
  +[![Build status](https://ci.appveyor.com/api/projects/status/nlso0s96wcuge2vn/branch/master?svg=true)](https://ci.appveyor.com/project/ringmesh/ringmesh/branch/master)
  +[![Build Status](https://travis-ci.org/ringmesh/RINGMesh.svg?branch=master)](https://travis-ci.org/ringmesh/RINGMesh)
  [![Coverage Status](https://coveralls.io/repos/bitbucket/ring_team/ringmeshcoverage/badge.svg?branch=default)](https://coveralls.io/bitbucket/ring_team/ringmeshcoverage?branch=default)
  RINGMesh is tested under Linux (64 bits) and Windows (64 bits).
  You will need CMake (version >= 2.8.11). There is no other dependency (everything
  you need is shipped with RINGMesh). Follow the Linux, Mac OS or Windows instructions below.
  -To clone RINGMesh you need Mercurial (https://www.mercurial-scm.org/).
  -You also need to have Git (https://git-scm.com/) for RINGMesh subrepositories (without it the cloning will fail).
  +To clone RINGMesh you need Git (https://git-scm.com/).
  Make sure that Git binary directory is in your computer path (environment variable).
  Under Windows, after installing Git you should have in your path environment variable:
  C:\Program Files\Git\cmd.
  -Warning: TortoiseGit (https://tortoisegit.org/) does not install Git, whereas
  -TortoiseHg (https://www.mercurial-scm.org/wiki/TortoiseHg) installs Mercurial (tested on Windows 10).
  +Warning: TortoiseGit (https://tortoisegit.org/) does not install Git.
  Linux
  ===========================
  