Refactored the I2NP::Message code (yay!).
Removed the second template parameter on StaticByteArray because it was
useless.
Added I2NP::Garlic (not implemented yet).
All modifications are presently untested.
Added DatabaseStore to I2NP::Message.
Small fixes.
Merge branch 'master' of http://git.repo.i2p/r/i2pcpp