Add test for findAndCountAll with required belongsTo and limit

Test currently fails. See issue #1953.
restore breaking test
added pretty complicated case, that fails at the moment
fixed pretty complicated test
small fix, and prittified indentation a bit
Merge branch 'master' into associating-sections-when-deletions

* master:
  Allow removing has-many associations by id
  Update README.md
  #2338 - Associations remove[AS][plural]
  Use the new beta build env on Travis
  Text fix
  More promises
  Promisify tests
  Remove unnecssarily asynchronous tests
  Update changelog with BC breaking hstore change
  Update json test expectation
  Merge fix
  Update pg-hstore
  Removed no longer supported nested hstore objects from tests. Improved hstore array handling.
  Use pg-hstore for hstore parsing
  Hstore empty string tests
fixed indentations
Add test that ensures allowNull

This commit adds a test that checks allowNull in combination with
primaryKey.
add ability to test for dialect transaction support

Transaction support is currently very limited in the MSSQL dialect,
this allows us to conditionally skip transaction related tests for
a given dialect. I imagine it's also a nice feature to have when
adding a new dialect, so you don't have to solve all one thousand
errors at the same time
refactor(instance): .save(fields, options) -> .save(options)
feat(instance): .save (when an update) will now use an intersection of changed and attributes as fields
Merge pull request #2654 from mbroadst/transaction-support

add ability to test for dialect transaction support
fix(Model): add support for destroys on models without primary keys, fixes #2561
Merge branch 'master' of github.com:sequelize/sequelize
fix tests that i broke
fix(transaction): reject transaction promise when transaction callback does not result in a promise chain
Merge branch 'associating-sections-when-deletions' of https://github.com/vpontis/sequelize into vpontis-associating-sections-when-deletions
test(hasMany/include): add test by vpontis
Merge branch 'vpontis-associating-sections-when-deletions'
Fix increment and decrement usage with schemata