Fix syntax

GeoModelXML/README.md

@@ -14,7 +14,7 @@ https://twiki.atlas-canada.ca/pub/AtlasCanada/ITk/gmx2geo.pdf
 
 If `GeoModel` is installed:
 
-```
+```bash
 # Clone
 git clone ssh://git@gitlab.cern.ch:7999/atlas/geomodelatlas/GeoModelATLAS.git
 
@@ -29,11 +29,11 @@ cd ..
 
 ### Post-build setup
 
-**NOTE:** This is only needed on macOS, and only when using a local `install` folder (instead of system folders like `usr/local/`). 
+**NOTE:** This is needed **on macOS only**, and only when using a **local** `install` folder (instead of system folders like `usr/local/`). 
 
 This extra step tells the `GMXPlugin` where it can find the other libraries, when loaded as a plugin at runtime:
 
-```
+```bash
 # EXTRA STEP: Add a rpath, only needed on macOS and when using a local 'install' folder 
 install_name_tool -add_rpath install/lib install/lib/libGMXPlugin.dylib
 ```
@@ -41,13 +41,14 @@ install_name_tool -add_rpath install/lib install/lib/libGMXPlugin.dylib
 ## How to run it
 
 Running the GMXPlugin executes the xerces parser to parse the xml file. The expression evaluator only works if the system language is set to USEnglish, thus do:
+
 ```bash
 export LANG=en_US.UTF-8
 ```
 
 From e.g. your home directory
 
-```
+```bash
 cd install
 export GMX_FILES="../GeoModelATLAS/GeoModelXML/data/example1.xml"
 bin/gmex lib/libGMXPlugin.1.0.0.dylib (or .so on Linux)
@@ -58,7 +59,7 @@ Once `gmex` is open, click on the **Geo** tab, then check **DisplacedTube** and
 
 You can also display several `.xml` files at once by exporting a space separated string:
 
-```
+```bash
 cd install
 export GMX_FILES="../GeoModelATLAS/GeoModelXml/data/example1.xml ../GeoModelATLAS/GeoModelXml/data/example2.xml ../GeoModelATLAS/GeoModelXml/data/example3.xml"
 bin/gmex lib/libGMXPlugin.1.0.0.dylib (or .so on Linux)