Confusing error message for selected date before current

[Philipp Blum]

Steps to reproduce:

1. Create a task with some title.
2. Select a date which is before the current one.
3. Add description
4. Click on save

Actual behavior:
Error message in frontend: "Error in task submission". Error in terminal: "Task due date cannot be earlier than the current date."

Expected behavior:
Error message in frontend: "Task due date cannot be earlier than the current date.". Error in terminal: "Task due date cannot be earlier than the current date."

Tania version: 1.7.1

[Asep Bagja Priandana]

Thanks for noticing this one @Citrullin. I'll release a hotfix for this one.

[Philipp Blum]

@bepitulaz I added a comment to your commit. 966c9e6