Use org.bukkit.Color instead of TextColor in Text Hologram Background

[UsainSrht]

I'd recommend saving background field in only one way instead of transparent, green, #RRGGBB If that's okay I can create another pr for that.

[OakLoaf]

Do you think you could rename this or move the persistent related commits into a separate branch/pr. After you've done that I can review the PR

[OakLoaf]

Just making note that this PR would resolve https://github.com/FancyMcPlugins/FancyHolograms/pull/33

[UsainSrht]

Do you think you could rename this or move the persistent related commits into a separate branch/pr. After you've done that I can review the PR

Yeah I accidentally committed persistent holograms here too, I'll create two different branches for these two features.

[UsainSrht]

separated as #95 & #96