[README] Fix indentation

Make the README file 'github'-like

README.md

@@ -20,29 +20,27 @@ built with glibc 2.22.. We are trying to print, by using Multiarch GNU GDB,
 the value of the TLS variable (declared as __thread int foo = 0xdeadbeef;) from
 a core file generated on a target machine.)
 
-
-./gdb
-...
-(gdb) add-auto-load-safe-path ~/path_to_the_glibc22_build/INSTALL/lib
-(gdb) set libthread-db-search-path ~/path_to_the_glibc22_build/INSTALL/lib
-(gdb) set solib-search-path ~/path_to_libs_from_target_machine/
-(gdb) file exampleFromMipsPlatform
-Reading symbols from exampleFromMipsPlatform...done.
-(gdb) core-file core.mips
-...
-[Thread debugging using libthread_db enabled]
-Using host libthread_db library "~/path_to_the_glibc22_build/INSTALL/liblibthread_db.so.1".
-Core was generated by `./exampleFromMipsPlatform'.
-Program terminated with signal SIGABRT, Aborted.
-#0  0x00000000 in ?? ()
-[Current thread is 1 (Thread 0x771bf000 (LWP 21808))]
-
+	...
+
+	(gdb) add-auto-load-safe-path ~/path_to_the_glibc22_build/INSTALL/lib
+	(gdb) set libthread-db-search-path ~/path_to_the_glibc22_build/INSTALL/lib
+	(gdb) set solib-search-path ~/path_to_libs_from_target_machine/
+	(gdb) file exampleFromMipsPlatform
+	Reading symbols from exampleFromMipsPlatform...done.
+	(gdb) core-file core.mips
+	[Thread debugging using libthread_db enabled]
+	Using host libthread_db library "~/path_to_the_glibc22_build/INSTALL/liblibthread_db.so.1".
+	Core was generated by `./exampleFromMipsPlatform'.
+	Program terminated with signal SIGABRT, Aborted.
+	#0  0x00000000 in ?? ()
+	[Current thread is 1 (Thread 0x771bf000 (LWP 21808))]
 
 -before patching:
-(gdb) p/x foo
-Cannot find user-level thread for LWP 21808: generic error
 
+	(gdb) p/x foo
+	Cannot find user-level thread for LWP 21808: generic error
 
 -after pathing:
-(gdb) p/x foo
-$1 = 0xdeadbeef
+
+	(gdb) p/x foo
+	$1 = 0xdeadbeef