Theme relevant changes since beta 3

I will try to keep this updated as new changes occur.

This is a list of API changes that have occurred since beta 3.
Some are function names, some are message names, some are new classes. Function names are grouped by the class they were added to.
Check Docs/Luadoc/Lua.xml for detailed documentation on the functions.

Actor - texturetranslate added.
ActorFrame - GetChildren and GetChild changed to return a table when multiple children have the same name.
ActorMultiVertex - new actor class, Def.ActorMultiVertex. ScreenAMVTest is the usage example.
ActorScroller - SetDrawByZPosition can now be used without turning off Loop.
CodeDetector - Pad codes in dance mod that set harmful modifiers disabled. (technically not merged, seems to have enough support to merge soon)
CurrentSteps/TrailChangedMessage - no longer double broadcasts
CustomLoadFunction - Now runs when the theme is changed or when a local profile is assigned to a player.
GameSoundManager - SOUND:StopMusic added.
GameState - HaveProfileToLoad, HaveProfileToSave, LoadProfiles, SaveProfiles, GetSongOptionsObject, StoreRankingName added.
GetTimeSinceStart - New global function.
HighScoreList - GetHighestScoreOfName and GetRankOfName added.
JudgmentMessage - FirstTrack parameter added to mine cases, Tracks parameter added to TapNoteScore cases.
NoteField - Properly added to the actor tree so it can be accessed as a child of the Player. Now allowed to be any actor.
NoteSkinManager - NOTESKIN:GetMetric added.
MMods - can now be changed midsong in a tweenable way the way xmods can.
PlayerOptions - new class, accessible through PlayerState:GetPlayerOptions
Profile - AddScreenshot, GetAllUsedHighScoreNames, GetHighScoreListIfExists, SetLastUsedHighScoreName added.
SaveScreenshot - New global function. (technically not yet merged, will probably be merged within the week)
ScreenGameplay - Various Haste mod functions added, see Themerdocs/haste.txt.
ScreenWithMenuElements - StartTransitioningScreen, SetAllowLateJoin added.
SongOptions - new class, accessible through GAMESTATE:GetSongOptionsObject
Style - GetColumnInfo and GetColumnDrawOrder added.
TapNoteScore_MissedHold added - Metrics: HoldJudgmentMissedHoldCommand, LifePercentChangeMissedHold, DeltaSecondsMissedHoldCommand, PercentScoreWeightMissedHold, GradeWeightMissedHold.
THEME - GetMetricNamesInGroup and GetStringNamesInGroup added.

NoteField - Properly added to the actor tree so it can be accessed as a child of the Player. Now allowed to be any actor.
To be more accurate, the notefield's child "Board" can now be any actor.

PlayerOptions - new class, accessible through PlayerState:GetPlayerOptions
That class existed before, the methods just didn't work right.

PlayerOptions - new class, accessible through PlayerState:GetPlayerOptions
That class existed before, the methods just didn't work right.
Practically none of the methods are the same as before, so it should be regarded as a new class. (87 out of the 92 functions are completely different in implementation and usage)
Also, "didn't work right" is putting it lightly when using it before wasn't safe at all and it couldn't do anything or tell you anything.