move include tools.mk in Makefile so all target is default
Merge pull request #46 from basho/bugfix/makefile-default-target

move include tools.mk in Makefile so all target is default

Reviewed-by: kellymclaughlin
Add replace_member test

Completely replace the root ensemble: root/2/3 -> 4/5/6
Then replace the new ensemble with the old members: 4/5/6 -> root/2/3.

Also add riak_ensemble_peer:tree_info/1 for debugging and add
replace_members_test to TESTS list.
Merge pull request #45 from basho/test/re-add-members

Add replace_member test

Reviewed-by: andrewjstone
Add developer documentation

This readme file explains riak_ensemble to developers wishing to
understand what the library does and how it is implemented in the code.
It is a guide for developers who wish to contribute or maintain it, with
hopefully plenty of explanations and diagrams to help them quickly grasp
all the information.

It also includes a script to help maintain references to functions in
the code.  Run the update-doc-lines make target after compiling the
library to update the markdown, then check in the changes.