Fixed bug with SceneCache animated object topology.

Previously, if the first topology hash matched the last topology hash, the animatedObjectTopology attribute would not be written, even if the hashes on the intermediate frames differed.
iterate active compilers
Merge pull request #222 from richardmonette/activeCompilers

iterate active compilers
Merge pull request #221 from andrewkaufman/changingTopoBug

Fixed bug with SceneCache animated object topology.
IE base builds have compiler version in the python path.

We need this now that we're doing non-app builds with multiple compilers.
Merge pull request #223 from andrewkaufman/multiCompiler

IE base builds have compiler version in the python path.
Adding double to the list of attributes that can be queried in scene shapes.
Added todo
Merge pull request #224 from valeriebernard/sceneShapeInterfaceDoubleAttr

Adding double to the list of attributes that can be queried in scene shapes
Updated changes and bumped minor version
Using platform independent variables when writing/loading values from StreamIndexedIO.

The changes in the file format introduced in Cortex 8 came with 32 bit values that were saved from "unsigned int" variables. But that is platform dependent.
They have been replaced now by int32_t to garantee that the files can be loaded on 32bit platform.

Added some extra checks to prevent these values to overflow, preventing corrupted files.
Addressing comments by John.
Merge pull request #227 from ldmoser/streamIndexedIOmultiPlatform

Using platform independent variables when writing/loading values from StreamIndexedIO
Making StreamIndexedIO::Node work as MemberData, where it holds a pointer to the global Index and to the low level DirectoryNode.
Adding a specific class for DirectoryNode that holds the information loaded from the index.
Adding a member m_nodeType in NodeBase to distinguish derived classes without adding virtual methods.
Replacing the std::map to a sorted vector and sorting by the m_name field.
Using char instead of the enums in the structs to compact members in one word.
Original struct sizes were StreamIndexedIO::Node 104 bytes and DataNode was 56.
Current struct sizes are DirectoryNode 56 and DataNode 40 bytes.
Changing StreamIndexedIO member from intrusive pointer to raw pointer.
This does not affect the class size and should not break binary compatibility.
As a consequence the Node class reduced from 32 bytes to 16 bytes (not derived from RefCounted anymore).
Fixing bug by checking if pointer is valid. Now all tests passing.
Adding SmallDataNode class (24 bytes long on 64bit machines) when the data is small enough and avoid the big DataNode struct (40 bytes).
Updating comment.
Adding a compact Node class for representing non-expanded subIndexes: SubIndexNode (24 bytes).

This helps on the memory requirements for opening a file with a large amount of stored Objects. In particular, large LinkedScenes.