add images of new space and improve info on how to find space

[alifeee]

new space images

images (maybe photospheres?) of new space could be put on:

https://www.sheffieldhackspace.org.uk/the-space/

improving access instructions

lots of people are confused about how to get in and where the space is

we should add some pictures like this (@alifeee has full-res photos) to help, probably to either https://www.sheffieldhackspace.org.uk/the-space/ or https://www.sheffieldhackspace.org.uk/joining/