* Use standard KC_ALGR, remove language-specific redefinitions
* Use ALGR instead of ALTGR in BÉPO and Canadian multilingual keymaps
* Remove BE_LALT, BE_LGUI aliases
* Add standard ALGR defition, remove (re)definitions from language files
* Use ALGR(kc) consistently in ALTGR(kc) aliases
* Non-Nordic keymaps should not use NO_ALGR
* Add standard KC_ALGR definition
* Update docs with ALGR and KC_ALGR
* Update SS_ALGR and ALGR_T aliases
* Clarify the license for files we have signoff on
* Update against the currently signed off files
* Remove unused and not clearly licensed headers
* Replace an #endif I accidentally removed while resolving merge conflicts
