Master represents development for 7.x branch (for now anyway).
Add contribution instructions.
Rename README.txt to README.md and start formatting as Markdown.
Switch to Markdown format
Update README.md

formatting fix
More readable table when reading unrendered markdown
Better links in CONTRIBUTING.md
Rename tests/README.txt to README.md
Reformat for Markdown
Copy relevant info from drupal.org/project/drush
Append logo to README
Move some steps to POST-INSTALL

These steps apply to PEAR and MANUAL installs. Also, move usage stats step to the end.
Master branch should be compatible with Drupal 8.
Don't define DRUPAL_ROOT in D8
Fix login during bootstrap for D8
Fix another ->name problem in D8 by creating a 'user' engine. We'll need to refine and use this everywhere.
Stop spewing status info during archive-dump.
Stop spewing status info during archive-dump.
Start testing master branch as well.
List master branch's test status in README.md