Add electromagnetism summary

It contains a summary of topics 1 through 4.

Change-Id: Id41a440f77d5b3c2ae52a10c3db1b5314bc8d777
8 files changed
tree: 4cb68f7661c34630284e6816ff957ccf97b8a592
  1. quad8/
  2. .gitignore
  3. .gitreview