Formatted building_software.md; added missing shell prefixes.

Closes #215.

doc.zih.tu-dresden.de/docs/software/building_software.md

 # Building Software
 
-While it is possible to do short compilations on the login nodes, it is
-generally considered good practice to use a job for that, especially
-when using many parallel make processes. Note that starting on December
-6th 2016, the /projects file system will be mounted read-only on all
-compute nodes in order to prevent users from doing large I/O there
-(which is what the /scratch is for). In consequence, you cannot compile
-in /projects within a job anymore. If you wish to install software for
-your project group anyway, you can use a build directory in the /scratch
-file system instead:
-
-Every sane build system should allow you to keep your source code tree
-and your build directory separate, some even demand them to be different
-directories. Plus, you can set your installation prefix (the target
-directory) back to your /projects folder and do the "make install" step
-on the login nodes.
-
-For instance, when using CMake and keeping your source in /projects, you
-could do the following:
-
-    # save path to your source directory:
-    export SRCDIR=/projects/p_myproject/mysource
-
-    # create a build directory in /scratch:
-    mkdir /scratch/p_myproject/mysoftware_build
-
-    # change to build directory within /scratch:
-    cd /scratch/p_myproject/mysoftware_build
-
-    # create Makefiles:
-    cmake -DCMAKE_INSTALL_PREFIX=/projects/p_myproject/mysoftware $SRCDIR
-
-    # build in a job:
-    srun --mem-per-cpu=1500 -c 12 --pty make -j 12
-
-    # do the install step on the login node again:
-    make install
-
-As a bonus, your compilation should also be faster in the parallel
-/scratch file system than it would be in the comparatively slow
-NFS-based /projects file system.
+While it is possible to do short compilations on the login nodes, it is generally considered good
+practice to use a job for that, especially when using many parallel make processes. Note that
+starting on December 6th 2016, the `/projects` filesystem will be mounted read-only on all compute
+nodes in order to prevent users from doing large I/O there (which is what the `/scratch` is for).
+In consequence, you cannot compile in `/projects` within a job anymore. If you wish to install
+software for your project group anyway, you can use a build directory in the `/scratch` filesystem
+instead:
+
+Every sane build system should allow you to keep your source code tree and your build directory
+separate, some even demand them to be different directories. Plus, you can set your installation
+prefix (the target directory) back to your `/projects` folder and do the "make install" step on the
+login nodes.
+
+For instance, when using CMake and keeping your source in `/projects`, you could do the following:
+
+```console
+# save path to your source directory:
+marie@login$ export SRCDIR=/projects/p_myproject/mysource
+
+# create a build directory in /scratch:
+marie@login$ mkdir /scratch/p_myproject/mysoftware_build
+
+# change to build directory within /scratch:
+marie@login$ cd /scratch/p_myproject/mysoftware_build
+
+# create Makefiles:
+marie@login$ cmake -DCMAKE_INSTALL_PREFIX=/projects/p_myproject/mysoftware $SRCDIR
+
+# build in a job:
+marie@login$ srun --mem-per-cpu=1500 --cpus-per-task=12 --pty make -j 12
+
+# do the install step on the login node again:
+marie@login$ make install
+```
+
+As a bonus, your compilation should also be faster in the parallel `/scratch` filesystem than it
+would be in the comparatively slow NFS-based `/projects` filesystem.