Added lerp, lerp_color, approach, and multiapproach lua functions.
Merge pull request #349 from kyzentun/LerpColor

Lerp and related math functions.
Fix P2 input when PlayerAutoplay in P1
Merge pull request #352 from hanubeki/input-p2

Fix P2 input when PlayerAutoplay in P1
Lineage reporting for nil commands in RunCommands.  Stricter type checking for FormatPercentScore in PercentageDisplay.
Changed ColorToHex to just use string.format instead of useless number to hexstring to number to hexstring conversion.
Fixed broken else-if chain in Actor::SetEffectClockString.  Changed error to not crash Stepmania.
Minor docs change for effect colors.
Merge pull request #1 from stepmania/master

Update
Preserves backwards compatibility with 10.6

sync_volume_np was introduced in the 10.8 SDK. This commit ensures that
some related constants are defined before calling the function. If they
are not, we fallback to the older logic.
Fixed coloring and cropping of RollingNumbers during tweens.
Fixed RollingNumbers to work with corner diffuse colors.  Changed diffuse loops to use NUM_DIFFUSE_COLORS instead of 4.
Created tween queue and functions for BitmapText so the stroke color can be tweened.
Merge pull request #362 from kyzentun/StrokeTween

Tweenable stroke color for BitmapText
Fixed ScreenPrompt::AnswerOnCommand metrics by calling LOAD_ALL_COMMANDS after the name was set.
en.ini: Fix "guage"
Merge pull request #365 from psmay/patch-1

en.ini: Fix "guage"
no more double "is", either.
Added functions to ActorUtil for converting the extension to a file type and changed various places that had lists of extensions to use ActorUtil instead of duplicating the list of extensions.  Added webm and wmv to list of video types.
DefaultFailType preference removed because DefaultModifiers was overriding it.  DefaultFailType ConfOptionRow now works by putting the fail type in DefaultModifiers.
Fixed double InitCommand bug in Foreground.
Disabled odd dimension check for screen texture.