Merge branch 'tbaudier-master-patch-29184' into 'master'

Update readme.md

See merge request tbaudier/gatecontrib!1

Author: tbaudier

readme.md

@@ -2,7 +2,7 @@
 
 **Warning** - This is a *user-oriented*, collaborative repository of Gate examples. The [OpenGate collaboration](http://www.opengatecollaboration.org/) is not responsible of any contents.
 
-**PLEASE INSTALL GIT-LFS FIRST: this is required !**
+**PLEASE INSTALL GIT-LFS FIRST: this is required !**  
 This repository contains data (binary files), stored with [git-lfs](https://git-lfs.github.com/) extension. For most modern Linux distributions there is a standard package for this, e.g. for Ubuntu/Debian do: `apt install git-lfs`. (If your OS does not have a standard package for git-lfs, then follow the installation instructions on the [git-lfs GitHub page](https://git-lfs.github.com/).) With git-lfs successfully installed, clone the `GateContrib` repository with the command `git lfs clone https://github.com/OpenGATE/GateContrib.git`. If you omit the `lfs` from the `git clone` command then the large binary files may not be downloaded correctly.
 
 [Gate](https://github.com/OpenGATE/Gate), based on [Geant4](https://geant4.web.cern.ch) library, allows to perform various Monte-Carlo simulations in the field of **medical physics**. [Gate](https://github.com/OpenGATE/Gate) can be used in numerous ways and for a lot of different applications. This repository contains [Gate](https://github.com/OpenGATE/Gate) simulation examples, mostly provided by users, in order to help sharing knowledge.
@@ -28,3 +28,12 @@ References collaboration papers:
 * 2011 http://www.ncbi.nlm.nih.gov/pubmed/21248393
 * 2014 http://www.ncbi.nlm.nih.gov/pubmed/24877844
 
+----
+**If you encounter some problem while pulling:**  
+The repository was rebased in October 2020. So you can face to pulling problems. You can try one of this solution:
+ - If you do not have any modification in your local folder, you can remove and clone again the repository
+ - If you do not want to remove your local folder, you can try `git reset --hard origin/master` to force the pull
+ - For expert, you can try to rebase your local commits with the current master branch  
+
+In any case, if you have some troubles, do not hesitate to send an issue via Github, we can help you.
+