Add language about submitting multiple times.  Fixes #1684
Merge pull request #52 from LegalizeAdulthood/multi-submit

Add language about submitting multiple times.  Fixes #1684
Match nitpicking docs with current behavior

In response to https://github.com/exercism/exercism.io/issues/1693
Merge pull request #53 from sunzenshen/patch-1

Match nitpicking description with current behavior
Fix typo in git workflow page
Remove mdash