We already told you how to do it without custom spawn eggs.
OP is on 1.7.10 ... (seriously, update).
Did you seriously create a separate class for every. single. SpawnEgg?
Seriously?
You need one class and one Item. Store the type of Mob to spawn (it's String (!) ID) in the ItemStacks NBT data instead of taking up a gazillion Item IDs.
Also (again!): Do not use LanguageRegistry. Use a .lang file.
You don't need to make the Entity IDs configurable. It serves no purpose and just confuses users.
About all those addSpawn calls... You do know that addSpawn has a varargs parameter, right? Use it! (Don't know what varargs means? Learn java.)
First of all, there is no version of registerModEntity that takes the two color arguments for spawn eggs. I tried looking through the forge library and I couldn't find it. Second, these classes are not permanent, since I'm still figuring out how to use only one class (I'm making normal items and using the onItemUse method to spawn the mobs. It's the simplest way I found). Third, I am going to create the lang file, but I'm using the language registry method until I fix the spawn egg problem. One problem at a time. As for NBT and varargs, I am learning how to use Java as I'm working on this mod. I know basic to intermediate java, but there are also things in the language that I'm not familiar with. Could you guys post an example of the registerModEntity that takes the color arguments? That would really help.