Adds WJohnston's rainbow esword and dual-esword sprites.  Also corrected a few bugs involving esword sprites, mainly involving the player sprite not updating when they construct dual-eswords.  It turns out that player-sprite updating is magnets, so the eventual solution was for the player to drop both swords before they're deleted.  Since dual-eswords were already created on the ground, this changes very little.
A dual-esword inherits the emagged state of the esword being attack_by'd.
WJohnston updated the sprites with a 50% longer timing.
Finally finished adding double-toy-swords, emagged double-toy-swords, and improved some of the earlier fixes.  Swords no longer have to be turned off before emagging, the player-sprite overlay will update correctly now.
Merge branch 'master' of https://github.com/tgstation/-tg-station into RainbowSwords
Merge branch 'master' of https://github.com/tgstation/-tg-station into RainbowSwords

Conflicts:
	code/game/objects/items/weapons/twohanded.dm
	config/admins.txt
	icons/mob/items_lefthand.dmi
	icons/mob/items_righthand.dmi
Should bring admins.txt in line with tgstation upstream, and the icon files match the upstream ones too.  The icon files do still need to be edited, of course.
Resets weapons.dmi and tgstation.dme, meaning that the only diffs are to the code .dms (and those changes should be correct).  Next commit will handle adding the icons back to the synced .dmis.
Used Aranclanos's code for combining swords without dropping both hands!  Re-added the icons to the fresh DMIs.  Self-testing found no issues, this is ready for someone to approve.
Removed optional use of .src for Aranclanos
It's now hacking via multitool instead of emagging via emag... maybe people will actually do this (:
Merge pull request #1412 from Rolan7/RainbowSwords

Rainbow swords