Implemented the robot's Memorize capability

It was implemented with a hard usage of regex to validate the user input on the fly in order to prevent user mistake.
It enables the usage of star wildcard ( * ) in the "When the user says" field, and this wildcard content can be retrieved both in "Memorize" field and in "Say" field, through the get star syntax: ${*index}, where index is an integer value greater than zero.
It also introduces the get syntax ${variableName} to retrieve the content of an variable created in "Memorize" field, for usage both in "Memorize" field itself and in "Say" field.

Since now, you can do something like:

When the user says:
My name is *, I am * years old and I live in *.
Responding to:
Talk me about you
Memorize:
name=${*1}
age=${*2}
lives_in={*3}
Say:
Ok. I will remember that your name is ${name}, you are ${age} years old and that you live in ${lives_in}.
Ok, ${name}. I will remember that you are ${age} years old and that you live in ${lives_in}.