added readme for all templates and incorporated donnas PR feedback

Overhauled readme for main repo and events template and added
screenshots.

text change

added "see template specific readme.md in subfolders"

formatting changes

added breaks ect

changed preview link

formatting changes v2

added "-"

heading formatting

formatting changes v3

formatting changes v4

initial restaurant-promotion readme commit

readme image commits

initial restaurant-menuboard readme commit

main read me final tweaks

main read me final tweaks v2

events readme final tweaks

menuboard readme final tweaks

fixed file ext

restaurant promotions final tweaks

readme final tweaks

changed copy capitalized readme.md

Changes per donna review

removed bridge sort file and italics