Update documentation

README.md

@@ -14,20 +14,27 @@ Disclaimer: the DPI library is supplied with a modified version of Mercury 6 for
 The use of DPI in conjunction with Mercury 6 should be straightforward for Mercury's users. Users not familiar with Mercury 6 are advised to first read Mercury's manual to get in touch with its working.
 
 In order to use Mercury together with DPI the users need to compile together the following two files:
-- dpi1_0.for, containing the DPI library
-- mercury6_2-dpi.for, containing a modified version of Mercury 6 adapted to call the subroutines provided by the DPI library
+
+*  dpi1_0.for, containing the DPI library
+* mercury6_2-dpi.for, containing a modified version of Mercury 6 adapted to call the subroutines provided by the DPI library
 
 The two files can either be compiled together, e.g:
 
-gfortran mercury6_2-dpi.for dpi-rc2.for -o executablename
+```bash
+$>gfortran mercury6_2-dpi.for dpi-rc2.for -o executablename
+```
 
 or separately by using the option "-c" to create binary object files, e.g.:
 
-gfortran -c mercury6_2-dpi.for
-gfortran -c dpi1_0.for
-gfortran mercury6_2-dpi.o dpi1_0.o -o executablename
+
+```bash
+$>gfortran -c mercury6_2-dpi.for
+$>gfortran -c dpi1_0.for
+$>gfortran mercury6_2-dpi.o dpi1_0.o -o executablename
+```
 
 Once compiled, to use the S-type symplectic mapping:
+
 - create a file big.in with the bodies you want to integrate, taking care that the binary companion is the last body listed
 - indicate "wb" (wide binary, since the binary star is the outermost body of the system) as the algorithm in the file param.in of Mercury