v1.27

- Small fixes
- New feature to limit assignment to one task per user per day.
- added task creator name on the planning. Displayed when mouse is over the task.
- Added sorting option : can now sort the planning by name (project or user), id, team, group of project. If team or group, their name is also displayed as a separator in the planning.
- Added new option to display planning header (months/days) every x lines.
- Added milestone : can create a task as a milestone, displayed with specific icon in the planning. Also added to Gantt export.
- Added task status : to do, in progress, done, abandoned. Done and abandoned tasks are displayed crossed
- Added also a filter in the planning to display only status selected.
- Added repetition information in the email notification
- Fix bug on task creation : end repetition datepicker was never closed
- Dropdown added on title field when creating a task, in order to display existing titles for the same project.
