Updated documentation to reflect new build process

Updated the readme to reflect the new build script and the extra step
needed for packaging (passing in the 'package' task).

It also looks like the build/test xml output was not listed in the
.gitignore. I've added that but I wasn't quite sure if it's needed as an
artifact downstream.
Merge pull request #260 from hyrmn/updatedocs

Updated readme.markdown to reflect new build process
CommonDomain brought in from joliver/CommonDomain - Initial stab at #261

This is an initial import of CommonDomain into NEventStore/CommonDomain.
The goal was to minimize breaking changes for existing CD users who aren't
quite ready to string all the things.

Outstanding issues / work / request for feedback:

- EventStoreRepository tracks opened snapshots and streams in a local
  dictionary. The key was a guid and came from the IAggregate.Id. It's now
  a string of bucketId and IAggregate.Id. This seems really naive. Since
  IAggregate.Id is still a Guid, this could stay as a Guid as well. Or,
  some sort of Value Object wrapper around bucketId and IAggregate.Id
  might be in order.

_ IRepository allows for loading / saving with or without a bucket

- The SagaEventStoreRepository is untouched. I haven't used CD for saga
  work so I'm unsure if adding bucketId as a saga parameter is something
  people want. I assume so, but I didn't want to add it without some
  validation

- I believe I applied the NES code style formatting to all files.
Add test to create multiple streams on seperate threads and in a transaction scope.
Merge pull request #262 from hyrmn/commondomain

CommonDomain brought in from joliver/CommonDomain - Initial stab at #261
Merge branch 'master' into StressTest
Postgres - change Commits PK to CheckpointNumber and add unique index for (BucketId, StreamId, CommitSequence)
Oracle - change Commits PK to CheckpointNumber and add unique index for (BucketId, StreamId, CommitSequence)
Sqlite - add unique index for (BucketId, StreamId, CommitSequence)
fixed Guard check
added failing test for checkpoint counter initlialization
removed checkpoint initialization, increment is an upsert
Merge pull request #263 from seburgi/master

fixed Guard check
Merge pull request #269 from andreabalducci/mongoproviderfix

[Mongo] Checkpoint reset on Initialize
added unique index for CheckpointNumber
Merge pull request #270 from andreabalducci/missingindex

added unique index for CheckpointNumber
Merge branch 'master' of https://github.com/NEventStore/NEventStore