README: build instructions, sample run

README.md

@@ -33,6 +33,7 @@ healpix_fermi_intensity_skymap.cc
    Requires HealPix v3.11  available from http://healpix.jpl.nasa.gov/
 
    Usage: 
+
     ./healpix_fermi_intensity_skymap  counts_filename  exposure_filename  FWHM  prefix
 
                   counts_filename   input HealPix  counts file   (may be .gz, in which case the output file is also .gz)
@@ -43,7 +44,8 @@ healpix_fermi_intensity_skymap.cc
                  
    Restrictions: must be run in same directory as input files since output filenames are based on input filenames
    
-   The maps can be viewed, rotated etc with the Aladin programme provided by CDS Strasbourg. Energies are selected by columns using 'Edit>Preferences'.
+   The maps can be viewed, rotated etc with the Aladin programme provided by CDS Strasbourg.
+   Energies are selected by columns using 'Edit>Preferences'.
    Note Aladin will read .gz files.
 
    Version 1.0
@@ -82,6 +84,7 @@ exposure_healpix_full_clean_gt20MeV.fits
 
 
 run command:
+
    ./healpix_fermi_intensity_skymap  counts_healpix_full_clean_gt20MeV.fits exposure_healpix_full_clean_gt20MeV.fits 1 test
 
 Output files: