linkage: disable threading on legacy games

combat: force grenade war if have only grenade in hands

fix: crash bug when in some situations sv_gravity is zero

crlib: update submodule

fix: crash with menus and commands (resolves #292)

add: new regamedll entity to legacy linkents

fix: print queue isn't resetted on changelevel (fix #314)

package: fixed url list for graph [skip ci]

update: bump the year

Refactoring (#246)

add: yb_chat_percent, yb_camping_time_[min/max], yb_danger_factor[min/max], yb_chat_percent cvars
fix: possible crash with difficulty 0
fix: debug_goal should not be used as last history
fix:  startup on old hlds, because of missing pfnGetFileSize
fix: crash with out-bounds read
change: again tweaked some aiming code
change: player avoidance code so bots will jump less when stuck
change: max followers is just /4 of max players
refactor: redone distance between vectors
refactor: remove magic numbers in graph.add function

build: add arm64 build to linux release package

add: yb_ignore_objectives, that makes bots to ignore map target (hostage rescue, bomb plant/defuse) (fixes #237)
fix: possible buffer overrun in message functions
build: cleanup package.py