Add country Lithuania (LT)

The following list of holidays needs to be verified/completed:
|Date | Flags | Name|
| --- | --- | --- |
| 01-01 | [NF] | Naujieji metai |
| 02-16 | [NF] | Lietuvos valstybės atkūrimo diena |
| 03-11 | [NF] | Lietuvos nepriklausomybės atkūrimo diena |
| 05-01 | [NF] | Tarptautinė darbo diena |
| 06-24 | [NF] | Joninės, Rasos |
| 07-06 | [NF] | Valstybės diena |
| 08-15 | [NRF] | Žolinė |
| 11-01 | [NRF] | Visų šventųjų diena |
| 12-24 | [NRF] | Šv. Kalėdos |
| 12-25 | [NRF] | Šv. Kalėdos |
| 12-26 | [NRF] | Šv. Kalėdos |
| | [NRV] | Velykos |
| | [NRV] | Velykos |

Checklist:
* What type is the easter date?
- [ ] orthodox
- [ ] western
- [ ] All holidays (i.e. days "which are defined by law on which business or work are suspended or reduced") are listed
- [ ] Legal sources which define the holidays are provided
- [ ] The spelling of the holiday names is correct
- [ ] The given dates (independent of year) of the holidays are correct

Start by inspecting how existing country holiday definitions and their tests are organized, then verify Lithuania’s statutory holidays, names, fixed dates, legal sources, and Easter convention against authoritative references. Done means the Lithuania calendar is complete, accurate, and its checklist items are resolved with the required sources and tests updated.

Written by the indexing model from the issue text.