Remove drop shadow from badnik explosions, give drop shadows to Metal and flickies

Closes #218

See merge request STJr/SRB2!1761

Make S_IVSP and  S_THUNDERCOIN_SPARK fullbright

See merge request STJr/SRB2!1755

Make P_SpawnGhostMobj ghosts properly copy spritestuff2 (!1257) variables

See merge request !1741

Level platter name improvements

See merge request STJr/SRB2!1730

Fix typo in linux-only compilation flag

See merge request !1759

Remove MODID check from hooklib to fix compile issue (resolves #809)

See merge request !1758

- Added A_SetShadowScale
- Added A_ShadowScream which combines the above with A_Scream, used for 
badnik explosions
- Gave flickies drop shadows

Update Nightopians & other state changes

See merge request STJr/SRB2!1744

Tutorial scenery

See merge request !1722

Fix #805

Closes #805

See merge request !1757

Spawn MT_RAY when attempting to spawn MT_NULL

Closes #801 and #800

See merge request !1751

2022

See merge request STJr/SRB2!1754

Fix warning when compiling with NONET=1

See merge request !1753

Fix perfstats failing to compile with NOHW=1

See merge request !1728

Turn the console warning into a devmode print because turns out it happens more often than I thought

Some code assumes that P_SpawnMobj can never return NULL
So spawn MT_RAY in it's place when attempting to spawn MT_NULL and show a console warning

Move MT_RAY to the very end of the mobj list

See merge request !1747

Convert old frame flags in Metal recordings to their 2.2.10 equivalents

Closes #775

See merge request !1742

This reverts commit b2d693a5.

Fix blendmode V_ flags not working at full opacity in Software

See merge request !1717

Remove MT_NULL hacks

Closes #721

See merge request STJr/SRB2!1729

Increase Eggman's hitboxes

See merge request !1706

Improve bots (resolves #710)

Closes #710

See merge request STJr/SRB2!1679

Fix portals

See merge request STJr/SRB2!1724