Add lcal, a tui calendar app with timezone support

[Law-Chun-Man]

Hi, I would like to add lcal (https://github.com/Law-Chun-Man/lcal), this is a tui calendar app I wrote in this weekend.

The reason I wrote this programme is that I notice other popular terminal calendar (like calcurse and calcure) do not have time zone support. For holidays, they either do not support, or require internet/extra module. They do not accept ics for holidays.

Also, they do not support changing the file format of the todo note. My code allow user to define file format when editing todo note and event description, like .md, .rst, .txt, one can even use html as the file format. One can also easily define editor for editing todo note and event description, like nano, emacs or micro.

Adding this programme to your list will be greatly appreciated. Thanks!