added instructions on how to use eucalyptus
added virtualbox provider quickstart
silkysun comments`s addressed
Merge pull request #95 from jclouds/euca

added instructions on how to use eucalyptus and walrus
An Introduction to Guava and Guice
Update providers for 1.6. Consolidate providers/APIs onto one page.
updated release notes
doc updates for 1.5.7
Merge pull request #98 from rackspace/provider-cleanup-for-1.6

Update providers for 1.6. Consolidate providers/APIs onto one page.
Merge pull request #97 from andreaturli/master

virtualbox README updated
Merge pull request #103 from jclouds/1.5.7

doc updates for 1.5.7
output broke parsing