Added a module system
* Refactored init and save in a Main class
* Added a loader that keeps track of every file and load the module
* Added proper identifaction (Each module is given a auto increment
  ID by the loader (maybe should go in Main class?) and Tasks are
  given a complete id (of the form '{mod_id}.{task_id}')
* No more ID conflicting in Date Manager
* Refactored the next day part (when switching day)
* Refactored a part of task class in a Abstract base class
  (thinking of using a mixin here instead of subclassing)
** Coming next, adding a render for the calendar module
   Thinking of outputing in a file and using git push to save each day..?
 - Adding regular expression to edit desc or reflex and split tasks
 - Reorganise the rendering, add proper management of status so Tm.render
   only gives you what is relevant
 - A couple more things!
Love.