Multiple folder initializers

[bcharp]

Hi,

In a transition step from a monolith to something a little more micro, we needed to be able to import multiple folders with bootable initializers.

It works by passing an Array to bootable.initializers (or dirname:Array).

Would you like to merge it ?
I have run test on node 4.x and 0.10.x.

[coveralls]

Coverage increased (+0.4%) to 97.917% when pulling 2a7fd97 on bcharp:multiple_folder_initializers into 87d4b3f on jaredhanson:master.

[bcharp]

I seem to have some error not catch by tests. Investigating.

[coveralls]

Coverage increased (+0.5%) to 98.02% when pulling 298c941 on bcharp:multiple_folder_initializers into 87d4b3f on jaredhanson:master.