Improving Gerrit support.

Gerrit events now have:

• Events and callbacks methods added
• IRC notification on patchset created and comment added tested
• package require json

New procs in core:

• proc numeric2ordinal -> gets a ordinal from a number
• proc numeric2en (by RS) -> gets the english name from a number

Fixing bug:

• putdebug didn't distinguish a call without argument and a 0 char string to print