Added bold effect to some parts of the file

README.md

@@ -56,7 +56,7 @@ ansible
        |_ postgresql
 ```
 
-N.B: privilege escalation (sudo) relies on the "ansible_become_password" variable in group_vars/all/var_pass.yml file (it should be vaulted):
+**N.B:** privilege escalation (sudo) relies on the "ansible_become_password" variable in group_vars/all/var_pass.yml file (it should be vaulted):
 
 ```bash
 cd ansible/group_vars/all/
@@ -71,7 +71,7 @@ ansible_become_password: your password to become root on the target machines
 ...
 ```
 
-N.B: The provider / consumer installation mode is handled with the "irods_server_mode" variable in host_vars/myhost1.mydomain.tld file:
+**N.B:** The provider / consumer installation mode is handled with the "irods_server_mode" variable in host_vars/myhost1.mydomain.tld file:
 
 ```
 irods_server_mode: provider
@@ -181,7 +181,7 @@ ssh-copy-id -i /home/user/.ssh/ansible_id_rsa.pub user@myhost1.mydomain.tld
 ssh-copy-id -i /home/user/.ssh/ansible_id_rsa.pub user@myhost2.mydomain.tld
 
 ```
-N.B: if SELinux is set to "enforcing", please don't forget to run "/usr/sbin/restorecon -r -v .ssh" on each target machine, else your public key won't work.
+**N.B:** if SELinux is set to "enforcing", please don't forget to run "/usr/sbin/restorecon -r -v .ssh" on each target machine, else your public key won't work.
 
 10. Run the playbook