Apothecary: tess2 iOS script update

[danoli3]

In line with the discussion @ openframeworks/apothecary#14
libc++ for all iOS libs by default now.

I've made the script customisable to build libstdc++ as well.

Adding this one first to get feedback before adding the others.

[ofTheo]

@danoli3 for iOS I find abstracting out the different archs and then looping through the archs a little easier/cleaner - this allows you to write less code and then only change the flags you need to change for each arch.

there is an example of that on these lines here ( for assimp ):
2574f98#diff-6be9255ae2687604951e5dcd266d296cR54

I loop through an array and then change some flags based on which arch.

[danoli3]

@ofTheo Yeah I was basing this off the initial FreeType way of doing things, got it working in a loop for the other libs. I'll change this to be looped.

[danoli3]

Closing this as have a new way of doing this.