We ask the developer to obtain his own api credentials, because
the bundled 'api_id' / 'api_hash' are strictly limited by the server.
The old credentials still could be used for test purposes,
but the developer will need to explicitly opt-in to use them.
To be able to run on the same distributions as before we need to have
the same GLIBC version dependency as in Ubuntu 12.04, which is 2.15.
For that we need to remove all usages of GLIBC features from 2.16 and above.
Currently there are three methods used, so they're wrapped in a separate
static library, linux_glibc_wraps.
It is a separate library because it must be compiled without '-flto' flag,
otherwise the inline __asm__ is not working and we get unresolved symbols.
After adding the libtgvoip submodule its project was created by GYP
outside the project folder, because the relative path to libtgvoip.gyp
is "../ThirdParty/libtgvoip/" and projects are created in the same
relative folders.
Now we place MSVC and Xcode projects in tdesktop/Telegram, so the
libtgvoip project is created at tdesktop/ThirdParty/libtgvoip.
