Rubocop cleanup

This is all style cleanup based on Rubocop. I did adjust rubocop slightly (see below). These are standard rules we use for many cookbooks at Rackspace.
```
# Agree to disagree with rubocop on some specific rules

# Disable requirement of "encoding" headers on files, will go away with ruby 2.0 anyway
Encoding:
  Enabled: false

# Increase line length, we're not on VT220s anymore
LineLength:
  Max: 180

# Increase allowed lines in a method.  Short methods are good, but 10 lines
#   is a bit too low.
MethodLength:
  Max: 40

# Favor explicit over implicit code: don't complain of "redundant returns"
RedundantReturn:
  Enabled: false

# Raise allowed CyclomaticComplexity to 10.
CyclomaticComplexity:
  Max: 10

# Disable Single Space before first arg
SingleSpaceBeforeFirstArg:
  Enabled: false

# Don't force a word array unless 5 elements
WordArray:
  MinSize: 5

# Don't complain about unused block args
UnusedBlockArgument:
  Enabled: false
```

Probably the worst rewrites were in the providers, as many of the methods were too long for rubocop. I'm not sure this has to make it in for 2.0.0, but it seems worth having.