WL#1660: MySQL Administrator - Library tasks for Table Editor and Database Sync for Workbench

write two library functions:

* return differences of two table structs in 2 trees so it is easy to display
the differences graphically (keep this as open as possible to deal with
Workbench models in the future, e.g. multible tables, stored proc, ..)

A bad example of the GUI:
http://www.fabforce.net/various/DBSyncPowerDesigner.jpg

We should make it more intuitive, seperate the "model side" and the "database
side" onto two tabs, have a list of tables/references/stored proc rather than
trees, ...

* The user can select, which actions should actually be executed. (for MySQL
Administrator only the "database side" is interesting, the other is hidden)

* The "database side" tree should now be used to create the alter table
statements which can be executed later. (The other tree should later be used to
modify the MySQL Workbench model)