Change-Id: I74b3f9fedd77294c53648f8eaa730d4a84917555

This is a massive commit which reorganizes the entire project structure
(although it is still monolithic), removes the Build classes, and
switches to Moxie, a smarter Ant build tookit based on the original
Gitblit Build classes.

The Ant build script will likely require additional fine-tuning, but
this is big step forward.

If this feature is enabled then permitted users can automatically create a
repository when pushing to one that does not yet exist.  Permitted users
are administrators and any user with the CREATE role.

If the pushing account is an administrator, the created repository may be
located in any folder/project space.  This reposiory will inherit the server's
default access restriction and authorization control.  The repository owner
will be the pushing account.

If the pushing account is a regular user with the CREATE role, the repository
can only be located in the account's personal folder (~username/myrepo.git).
This repository will be VIEW restricted and accessible by NAMED users.  The
repository owner will be the pushing account.

Implemented discrete repository access permissions to replace the
really primitive course-grained permissions used to this point.  This
implementation allows for finer-grained access control, but still
falls short of integrated, branch-based permissions sought by some.

Access permissions follow the conventions established by Gitosis and
Gitolite so they should feel immediately comfortable to experienced
users.  This permissions infrastructure is complete and works exactly as
expected.  Unfortunately, there is no ui in this commit to change
permissions, that will be forthcoming.  In the meantime, Gitblit
hot-reloads users.conf so the permissions can be manipulated at runtime
with a text editor.

The following per-repository permissions are now supported:
- V (view in web ui, RSS feeds, download zip)
- R (clone)
- RW (clone and push)
- RWC (clone and push with ref creation)
- RWD (clone and push with ref creation, deletion)
- RW+ (clone and push with ref creation, deletion, rewind)

And a users.conf entry looks something like this:

	[user "hannibal"]
		password = bossman
		repository = RWD:topsecret.git

Repository owners no longer have to be explicitly selected to grant
them access to Git, feeds, and zip downloads. Idea from Github/dadalar.

Reorganization of resources. Dropped most hard-coded webapp
configuration in favor of common web.xml file. Still contemplating
configuring git servlet from web.xml too.

Replaced servlet container basic authentication with a custom servlet
filter which performs the same function.  The advantage to this is
that the servlet container is now divorced from the webapp.

The login service (realm) also simplified a great deal and removes its
Jetty dependencies.

Additionally, the basic authorization pop-up will be displayed as
needed based on the repository's access restriction.  This was
necessary for view-restricted repositories with the RSS feature.  Its
also necessary for completely open repositories as before it would
prompt for credentials.

Improved feed syndication feature.