Add Caveats section to readme

Users that are unfamiliar with the project may find some aspects unintuitive.  We should try and warn them so that they can have a better experience 

These are all ways that users broke VVV while I was helping them at WordCamp Lancaster
Alter language a bit in common caveats section
Merge pull request #1 from jeremyfelt/patch-5

Alter language a bit in common caveats section
Merge pull request #291 from aaronjorbin/patch-4

Add Caveats section to readme
Update CHANGELOG with other 1.1 changes
Correct links in previous CHANGELOG notes
Update version to 1.1 in README
Merge pull request #292 from Varying-Vagrant-Vagrants/release-1.1

[PR] Release 1.1