[MODELLO-271] toString method is generated only of for identifier fields
add doc for generation of toString method
generate doc for model version 1.8.0
upgrade some plugins versions
initial checkin of JSON writer based on Jackson streaming APIs
JacksonWriter contructor was not added to source code
fixed Map/Properties key/value type casting
fixed object sequence JSON serialization
association.isOneMultiplicity requires field name
just properly relocated the imports in defined writer class
better exploded Map serialization as array of properties, such as

[
    {"key": "key1", "value": "value1"},
    {"key": "key2", "value": "value2"},
    ...
]
Initial version of JSON Modello reader based on Jackson Streaming APIs
Merge pull request #5 from simonetripodi/master

Provide JSON Reader/Writer generator relying on Jackson Streaming APIs
When this project was located at codehaus such paper was not needed so why here.
So merge !! 
Thanks Simone !!
initial contribution of YAML reader/writer generator based on SnakeYaml
streaming APIs
Merge pull request #6 from simonetripodi/master

Add YAML reader/writer generator based on SnakeYaml streaming APIs
moved Simone Tripodi between developers list
s/stax/snakeyaml
updated Jackson plugin documentation page
JSON non wrapped items have tag name identified by fieldTagName
valuesTagName field is not longer used
YAML non-wrapped items are identified by fieldTagName