Support cross-compiling for iOS (armv7)

They are, but accessing them through public API is possible only through Obj-C, which looks kind of [ugly](https://gist.github.com/vhbit/56a8a2f1d990bf050ec8) and I'm not sure if it actually worths it considering cmd line args could be used only while debugging on simulator and are actually used to debug Apple provided stuff which is unaccessible otherwise. I'm pretty sure that providing some additional parameters to Rust parts of the app could be done in more friendly fashion