Merge branch 'master' into devel after changes for heroku deployment
Added propagating tables names to relation model if they change

When user change name of table, it is propagated to relation model and saved
here. Close this issue in Readme.md.
Added disabling foreign key columns at table dialog
Added `Model` class, generating SQL moved to main script

Intance of class `Model` contains all tables and relations in current model.
Generating SQL reacts on event invoked by main toolbar.
Added `toJSON` methods of table and relation model, added relation model test
Added `toJSON` for Model class and tests for all its methods
Added new toolbar icons, modified CreateRelation tool, added new tool

Added self created toolbar icons. Added parameter identifying to constructor
of CreateRelation tool that defines which tool is default type of relation.
Added new tool to toolbar that creates non-identifying realation in default.
Fixed setting of child table columns when type of relation change
Added blind save-model tool into toolbar
Added route for saving stringified model to filesystem
Added `stylus` grunt task, changed url of toolbar bg image to local
Added blind upload of model
Added (and almost finished) loading model from file
Finished loading model from disk, fixed toJSON of table model

Loading of model from file completed and is working. Commented test data
because they are now loaded from file. Fixed `toJSON` method of table
model to not export columns created by relation.
Updated issuses list in Readme, fixed style of common toolbar icon
Fixed recounting position of relation

Position of relation connection points is recounted when columns list of
any from related tables change.
Changed select of database so to convert app to SPA

Select database dialog changed, all communication with server is through
XHRs now and only one view exists at application.
Added statusbar that displays selected db into toolbar, fixed stylus task

Added import of `nib` at stylus task. Added statusbar to the end of
toolbar. Statusbar displaysname and version of selected db  .
Fixed table dialog for a new table

Fixed listen for columns change at table dialog if created new empty
table.
Fixed lost of data when adding column, fixed allowing to not fill table name

Table dialog couldnt been confirmed without filled table name. Fixed lost
of data when new column is added at the end of table dialog columns.