Merge remote-tracking branch 'origin/master'

Conflicts:
	.classpath
	bin/MainGui$1.class
	bin/MainGui$SwingAction.class
	bin/MainGui.class
	bin/corepack/Cliente.class
	bin/corepack/Libreria.class
	bin/corepack/Libro.class
	bin/corepack/Material.class
	bin/corepack/Registro.class
	src/MainGui.java
	src/corepack/Cliente.java
	src/corepack/Libreria.java
	src/corepack/Libro.java
	src/corepack/Material.java
	src/corepack/Registro.java