Check not node in LiteralInCondition

Like the existing and/or check this is flawed, but will be improved upon soon.
Bump Parser dependency to 2.0.0.pre1
Make the DotPosition cop configurable

It now has a `Style` config which can have one of two values -
`leading` (the default) and `trailing`.
Correct the behavior of LiteralsInCondition

As @whitequark had correctly observed the logical expressions in the
condition had to be checked recursively for literals.
Bump version to 0.9.1
add --list-cops opt to display cop names when listing offences
Merge branch 'master' of https://github.com/sabat/rubocop