SERVER-2407 better support for 32-bit Linux with V8
SERVER-2407 support amd64 architecture
SERVER-7617 Use V8_SIMPLE_HEADER in V8Scope::hasOutOfMemoryException()

Use our standard macro to set our state in V8Scope::hasOutOfMemoryException()
before calling _context->HasOutOfMemoryException().
SERVER-7344 add interpreterVersion to shell and buildInfo

Add the ability to get a string for the JavaScript engine so that
scripts can know when they are running under SpiderMonkey versus V8.
The shell gets an 'interpreterVersion()' function that returns a string.
The 'buildInfo' command gets a new field named 'interpreterVersion'.
SpiderMonkey returns "SpiderMonkey 1.7"; V8 returns "V8 3.12.19".

Conflicts:
	src/mongo/db/dbcommands_generic.cpp