Fresh new plugins for err

A serie of new err plugins arrived :

A plugin that tells you when the bot saw somebody for the last time. For example : !seen bidule

A smart calculator based on qalculator,  Examples: !calc 5+2 !calc x²+x+1=5 !calc 5 in² = x cm²

It can give you the definition/synonymous of a word. Example !define fish

It can give you the weather at the given location for the next few days. Example:  !weather san francisco, CA

And now err provides a public plugins repository so in order to install a public one just install it by name :
!install err-calcbot

It is uber-simple to create a plugin so feel free to add your own creations and I will add them to the official repository !