It still uses it's own config file, but now uses the same command line stuff

So we now have the complete set of commands in one tool.
This uses the new Command infrastructure to do two way conversion between
flags as strings and as a structured parsed form.

first step to shell command line completion

So don't bother making it a parameter

Use the new cabal command line handling infrastructure. Use proper flag types
rather than strings. 
Drop support for per-package command line flags as it was generally agreed to
be confusing.

ByteString.Char8 treats files as text files, which are really different
on windows. We were getting CRLF translation in Windows which was messing
everything up, like saving & reading the index file.
So now only use BS.Char8 where necessary.

We only have one LICENCE file

ie make "cabal install xmonad" work ;-)
We were parsing unqalified package names as a dependency upon a specific but
empty version. That is treating "foo" as a dependency like "foo==".
We now treat unadroned package names as deps on any version.

Parse command line arguments as either Dependency or PackageIDentifier, to allow e.g. 'cabal install binary-0.3'.

Fixed error message when some depedencies couldn't be resolved. Before it used show on Dependency, not showDependency.
Using fail here produces things like:
cabal: user error (Unresolved dependencies: containers -any, array -any, bytestring >=0.9)
It would be nice to get rid of the "user error" here. 

Instead of parsing every .cabal file in the package list (which is very slow)
We now just get the package name and version and do a case-insensitive
substring search on the package name. The output format remains unchanged.
So we no longer search inside package descriptions.

The url part cannot contain any chars, since then we allow spaces and ',' and
thus break parsing of following repos.

The ConfigFlags now contain two different sets of install dirs, one for global and one for user installs.
This simplifies the install dirs handling a lot, and allows the user to specify both user and global install dirs in the config file, and chose installation type on the command line.
We now ignore the config file and command-line compiler flavor when choosing install directories, since that
is so messy. This might break installs with Hugs, but that requires testing.
The old code didn't work when the compiler was specified on the command-line anyway.

Set preifx to the global default when the config file says to do a global install. This still doesn't work if --global is given on the command line. Print the complete config if verbosity >= verbose. Don't save prefix to the config file, since that means we will use the user default even for global installs.

Change Cabal dep to >=1.2 now that the required patches are in the 1.2 branch. This should really be >= 1.2.1, but the version number of the 1.2 has not been bumped yet.

eg: "xmonad [0.1, 0.2, 0.3]" rather than "xmonad [0.1,0.2,0.3]"
it's just a tad easier to read.

We now ignore file not found errors when deleting the packages dir.
Otherwise when we clean and then clean again we get an exception since
the directory we're trying to delete has already been deleted.

Pass -vN rather that --verbose=N to SetupWrapper, since older versions required --verbosity rather that --verbose.