Datagrams: Use typedefs and #defines for variable-length types, and functions that are specific to those defines.
NetworkClient: Use new size types.
Globals: Use new size types.
MessageDirector: Use new size types.
PostRemoves: Add read_datagram to dgi that appropriately handles variable datagram size when reading nested datagrams.  Use blobs instead of strings for postremoves.
DatagramIterator: Fix get_<metadata>() and seek_payload() to use type-size constants.
AstronClient: Use new type-size constants.
ClientAgent: Use new type sizes.
Uberdogs: Move UD initialization from ClientAgent to Main
YAML Database: Use new type-size constants.
SociSQL Database: Use new type-size constants.
DatabaseServer: Use new type-size constants.
Merge branch 'master' into 128bit
Bugfixes: Fix problems with datagram overflowing and other size-based issues.
Stateserver: Use new size-type in SS and DBSS.
Add 32-bit option for datagrams to CMakeLists
DatagramIterator: Hack a fix for 32-bit length tags when adding post_removes.  A proper fix will have to come from protocol changes.
Fix datagram size reading.
Tests: Skip test for oversized fields updates when using 32-bit modes (will have to do slight proto-changes to address this)
Cherry-pick dbserver fix to resolve merge conflict.