Make the progress callback more useful
Add FileDownloadChunk callback called after sending ack

The current pnAuthClient::onFileDownloadChunk callback is called before sending the acknowledge message to the server. This callback is typically used to send the next command to the server. Some servers (notably MOSS) don’t like it if you request a new file before acknowledging receipt of the previous one. To handle that, the callback should be called after sending the ack message. To avoid disrupting functionality of existing library users, the existing onFileDownloadChunk method is left alone and a new additional method pnAuthClient::onFileDownloadChunkPostAck is introduced.
Fix debug build broken by 37ea10c
Fix truncation of short strings to half length on conversion to wide chars
Merge pull request #33 from cwalther/stringtrunc

Fix truncation of short plStrings to half length on conversion to wide chars
Merge pull request #31 from cwalther/downloadchunkpostack

Add FileDownloadChunk callback called after sending ack
Allow user-specified G values for encryption keys
Merge pull request #32 from cwalther/keyg

Allow user-specified G values for encryption keys
Unify onFileDownloadChunk variants, using only the post-ack version (it makes more sense than the pre-ack version)
Don't attempt to dereference a null plVolumeIsect creatable
Use LLVM's libc++ on Mac, since XCode's GNU libstdc++ is woefully outdated
Xcode apparently needs extra parameters --

The previous commit only fixed Makefile builds; this one allows the XCode
GUI to also build (and link) successfully with clang/libc++
Convert all instances of PyPlasma to PyHSPlasma

This fixes pydoc output.
Implement CompoundController->TMController
Implement TMController->CompoundController
Add virtual assignment operator for hsKeyFrames.

This addresses a bug manifesting in plLeafController as the default
behaviour only copied the base hsKeyFrame fields.