Add a guide on proposing design changes
Add a guide on proposing design changes

This is an adaptation of my post "So you fancy yourself a designer".

Fixes #213
jpcarvalho1992/mvp,learnercys/mvp,charanrajtc/mvp,jgabriellima/mvp,ericramirez/mvp,ethan42411/mvp,luiscauro/mvp,btkostner/mvp,Dazag/mvp,aleksandar-todorovic/mvp,isdampe/mvp,shockry/mvp,Dazag/mvp,charanrajtc/mvp,luiscauro/mvp,btkostner/mvp,arunlodhi/mvp,aleksandar-todorovic/mvp,arunlodhi/mvp,elementary/mvp,elementary/website,LinkBR/mvp,hyptos/mvp,Dazag/mvp,ericramirez/mvp,wakermahmud/mvp,hyptos/mvp,LinkBR/mvp,elementary/mvp,wakermahmud/mvp,luiscauro/mvp,Sesshoumaru404/mvp,ericramirez/mvp,wakermahmud/mvp,sineld/mvp,charanrajtc/mvp,arunlodhi/mvp,jpcarvalho1992/mvp,jgabriellima/mvp,elementary/mvp,shockry/mvp,elementary/website,Sesshoumaru404/mvp,shockry/mvp,LinkBR/mvp,elementary/website,learnercys/mvp,isdampe/mvp,ethan42411/mvp,sineld/mvp,btkostner/mvp,jpcarvalho1992/mvp,aleksandar-todorovic/mvp,hyptos/mvp,jgabriellima/mvp,ethan42411/mvp,learnercys/mvp,isdampe/mvp,Sesshoumaru404/mvp,sineld/mvp