added model interface - validation and hooks
database test - model
Merge branch 'f-model' into dev

* f-model:
  database test - model
  added model interface - validation and hooks
cursor functions
transactions improve and bug fix
Merge branch 'f-sess' into dev

* f-sess:
  transactions improve and bug fix
  cursor functions
Merge branch 'r-0.5'

* r-0.5:
  transactions improve and bug fix
  cursor functions
  database test - model
  added model interface - validation and hooks