Make add to mygetlist work
change rule of random id generation

Currently, the randomly generated item url, it's 9 digit random combination of 3 letters and 6 numbers as designation (the 3 letters and 6 numbers can be in any combination, can be repeated and the letters can be upper or lower case).

We will change it to:

9 digit random combination of letters and numbers as designation (it can be in any combination, any number of letters or numbers, can be repeated and the letters can be upper or lower case). So it can be aaaaaaaaa or 000000000 or AAAAAAAAA or V3h0wU6li or aaa000aaa.
Utility to clean bad pins from database
Removes user_prefered_pins table

This table is no longer used. This was created
for registration purposes, but not used anymore
Removes tables and data not used

Currently these tables are not being used, so
I remove them for the sake of understandability:
admin_roles
admin_users
admin_users_roles
pin_loader_log
Merge pull request #73 from camilotorresf/fixes

Random URL change and other fixes.