Add option for creating 32-bit build targets in tasks.json generator

Description:

We need to provide an option to create 32-bit target builds (passing b32 to the make/nmake command line) when generating tasks.json. This will be important for projects that are planning on porting to 64-bits, but need to resolve bit-depth issues first (ttFormBuilder is a good example of this).

Issue Type:

• Bug report
• Feature request
• Design change request
• Other