Migrate build system to ttk* tools

- Create .ttk configs
- Migrate old builkd_gaia.sh to ttk-build and use ttk.inc.sh helpers
- Use ttk-get and ttk-put
- Add new ignores
- Remove symlinks and rely on ttk language renaming
- Remove obsolete tools
Templates: update to latest
Templates: fix headers to be location agnostic
Welsh: pull from Pootle
Welsh: update to latest templates
[km] pull from Pootle
[km]: update against latest templates
[tr]: pull from Pootle
[tr]: update against templates
[ne]: pull from Pootle
[ne]: update against templates
[hy] Initialise
[id]: pull from Pootle
[id]: update against templates
[gd] pull from Pootle
[gd] update against templates
[si] pull from Pootle
[si] update against templates
[bn_IN,hy_AM,ps] update against templates
[ka ff ko ms sw th af] update against templates