Test for an empty string with `-z` rather than `-e`

Fixes the adding of vvv-hosts entries to the virtual machine, which has been broken since b669fd29e4 during an attempt to get better at empty and not empty checking.

In looking at this issue, it appears that `-e` is in use in a few places and I'm not entirely sure that it actually does anything. I'll fix those as well.
Merge pull request #228 from 10up/fix-vm-hosts

Test for an empty string with `-z` rather than `-e`
Remove defaults from my.cnf

Lots of defaults were set in the my.cnf file and as mysql versions increase, the syntax for the settings changes.  As we're  not purposely setting these values to anything particular, I've just deleted them in the my.cnf, which will use whatever default the current version of MySQL has.  I've left a few variables set in here that are relevant, such as max_allowed_packet.  I decided to remove things rather than comment them out because if you need that setting in this file, you know what you are doing enough to know where to put it without having a guide.  Having the values in there does more of a disservice I believe as it provides suggestions that have no relation to what you are trying to accomplish.  The items that are commented out and left in are things that could be toggled on and off to aide development. 

This is untested, but I'd be surprised if it caused any problems.
Update README and CHANGELOG for v1.0 release
Remove all unlink statements in provisioning

In v1.0 of VVV, we made the change to copy a bunch of config files over rather than using symlinks. Because of this we had to unlink all of the previous symlinks before the copies would actually work. The unlinking should be treated as a temporary solution as it is somewhat confusing to run across in the provisioning script.

This commit removes unlinking. If for some reason an upgrade is done from v0.9 directrly to v1.1 or master, it is possible that some errors will appear explaining that a file cannot be copied on top of itself. This isn't much of a big deal, but should be treated with a `vagrant destroy` and `vagrant up` to clear things a bit.
Update CHANGELOG and README for 1.1-working
Merge pull request #230 from 10up/remove-unlinks

Remove all unlink statements in provisioning
Fixed a Link in README.md

Under VVV as a Scaffold: The link to the Auto Site Setup wiki entry contained a "-" where should have been a "/".
Merge pull request #231 from selinerdominik/patch-1

Fixed a Link in README.md
Update contributors list
Add `index.html` to the list of expected index files. Fixes #223
Added VVV Wiki link re: PuTTY to README

Also cleaned up the wording in Prgrph 2 of the `Now What?` section.
Merge pull request #234 from ericandrewlewis/master

Add `index.html` to the list of expected index files. Fixes #223
Merge pull request #235 from vDevices/master

Added VVV Wiki link re: PuTTY to README
Update contributors list
Update new language around SSH access in Windows
Remove some detail around `vagrant destroy`

Over time it would be nice to forget about `vagrant destroy` as part of the workflow.
Remove attempt to use index.html other than as a fallback

If we have index.html in try_files, requests for files that should result in 404 somehow work into the same redirect loop that is described in http://core.trac.wordpress.org/ticket/20746

By leaving the other index.html line in the config, it is still used as the default fallback, there is just no need to use try_files in combo with it.

See #233
Merge branch 'master' of github.com:10up/varying-vagrant-vagrants

Conflicts:
	README.md
	provision/provision.sh
Remove nginx configuration as it's not needed