[Fuego] allow changing the port used by jenkins

[Daniel Sangorrin]

Hello Tim,

These patches for the fuego repository (next branch) allow users to specify their desired port for Jenkins when installing Fuego.

[PATCH 1/2] dockerfile: split release test instructions
[PATCH 2/2] port: allow users to choose a different port for jenkins

Note: you can find them on my repository (next branch)

Best regards
Daniel