IR: Fixed serialization of Core::Floats.

Also changed generic number deserialization to use Core::StringBuf to possibly be more efficient.
AS: Added Float literal support.
Bytecode::ZDACS: Added float literal output.

Added a hack to Core/Number.cpp to set the default floating precision, because the default default is worryingly low.
IR: Added float instructions.
Bytecode::ZDACS: Added float add/sub/neg.

Also added translations for other float operation calls, but no implementation yet.
Fixed a serious error in preStmntCall, which could add a function while the range of functions was being iterated over.
Fixed a stupid error in preFunc which failed to invoke preBlock.
libGDCC: Reorganized ZDACS assembly.
libGDCC: Implemented ZDACS float compares.
Bytecode::ZDACS: Added MuXU, DiX*, and Move_W4-6 instructions.

Redid trStmntStk3 to be able to handle different source and destination size.
libGDCC: Implemented ZDACS float multiply.
libGDCC: Added float division for ZDACS.
CC: Moved statics in Parse/Exp/Prim.cpp into namespace.
CC: Added fixed and floating constant parsing.
AS: Fixed float literals to apply exponent.
CC: Added floating-point conversion codegen.

Current solution results in a large amount of inline conversion code which may be undesirable if many conversions between float and fixed are needed. In the future, it may be preferable to dynamically generate conversion functions.
There are some unfortunate assumptions in the conversion logic. Most are non-issues with respect to expected future direction (signed floats, bitsF<wordBits, endianness), but there will need to be handling for fixed types with greater range than floating types eventually.
Added IR/ExpCode.hpp as an IR-level counterpart to AST/ExpCode.hpp (which now uses the former).
Added float exponent bias information to AST::Type.
Added move semantics to AST::Temporary, although it ended up being unnecessary.
CC: Implemented conversion to soft boolean for floats and more pointer types.
GDCC: Added doc/softfloats.txt.

File exists to document implementation of floating point, and a place to officially credit and thank MageofMystra for his C softfloat implementation.