v0.0.1, 2013-10-25 -- Initial release.
v0.0.2, 2013-10-25 -- Remove tests from distribution package.
v0.0.3, 2013-10-25 -- Debugging packaging errors.
v0.0.4, 2013-10-25 -- (Hopefully) fix packaging errors.
v0.0.5, ???        -- Various changes.
v0.0.6, ???        -- Various changes.
v0.0.7, ???        -- Various changes.
v1.0.0, 2013-12-17 -- Incompatible API Changes:
                        * (Issue #21) utf-8 encode StringFields
                        * (Issue #32) ListFields are now type checked
                        * Remove the concept of an EmbeddedField having an owner
                        * EmbeddedFields are set to None if no value is given
                        * Default value for EmbeddedFields are type checked.
                        * Allow IntegerFields, FloatFields and BooleanFields
                          to have None values if not required
                      
                      Backwards Compatible Changes:
                        * Documentation improvements
                        * Now building with Travis-CI
                        * Using flake8 for linting, complexity measurement
                        * Tests run with code coverage
                        * Various refactorings
                        * Now embedded fields can have default values.
                      
                      Backwards Compatible Bug Fixes:
                        * (Issue #33) The variable name of a field can be
                          different from document field name
                        * (Issue #37) Add encoding to all source files
v1.0.1, 2013-12-17 -- Backwards Compatible Bug Fixes:
                        * Fix bug where ListFields were not loaded from
                          MongoDB.
v1.0.2, 2014-02-11 -- Backwards Compatible Bug Fixes:
                        * (Issue #42) Include bson_id when serializing to JSON.
                        * (Issue #44) Required Fields with Default Values.
v.1.0.3, 2014-02-24 -- Forward Compatable Changes
                        * Dirty field checking
                        * Use "upsert" by default when updating
v.1.0.4, 2014-02-25 -- Forward Compatable Changes
                        * Test for Document#save "upsert"
                        * (Issue #49) Problems with boolean fields
v.1.1.0, 2014-04-29 -- Forward Compatible Changes
                        * Uses MongoReplicaSetClient if hostname includes
                          "replicaSet"
                        * (Issue #51) Model level validations
                        * Add write concern option support for Document#save
                        * (Issue #48) StringFields and non-string values
                        * Various documentation fixes and test clarifications
v.1.2.0, 2014-05-05 -- Forward Compatible Changes
                        * (Issue #3) Uniqueness Validation
v.1.2.1, 2014-05-14 -- Backwards Compatible Bug Fixes:
                        * StringFields can now handle values with unicode
                          characters that have been processed by a JSON parser.
v.1.2.2, 2014-10-23 -- Backwards Compatible Changes:
                        * If a tavi.Document is initialized with unknown 
                          kwargs, log them and their values.
v.1.3.0, 2014-12-04 -- Backwards Compatible Changes:
                        * A compound unique index is created when multiple
                          fields are specified as unique in a document.
