STY + ENH

Hi all, sorry for the delay -- I did not find time until now.
Here it comes: Besides ICA + logos I changed the color scheme a bit to let the poster appear more similar to the webpage, e.g. the mnewebblue, mneblue and mnered are hex-color-picked from the webpage background + the MNE helmet. I dropped the green because I found the poster too colorful. In case you prefer to keep the green we can use mnewebgreen which is hex-picked from the example python codes on our webpage.

I hope you're going to like it.

Denis