Linux - tecnicas para liberar espaço /boot

http://askubuntu.com/questions/89710/how-do-i-free-up-more-space-in-boot

https://aacable.wordpress.com/2017/10/02/safest-method-to-clean-boot-partition/

https://gist.github.com/ipbastola/2760cfc28be62a5ee10036851c654600