Improvements to JavaScript analysis

General improvements

Support for the following frameworks and libraries has been improved:
- cross-spawn
- cross-spawn-async
- exec
- execa
- exec-async
- express
- remote-exec
Support for tracking data flow and taint through getter functions (that is, functions that return a property of one of their arguments) and through the receiver object of method calls has been improved. This may produce more security alerts.
Taint tracking through object property names has been made more precise, resulting in fewer false positive results.

Query	Tags	Purpose

Query	Expected impact	Change
Shift out of range	Fewer false positive results	This rule now correctly handles BigInt shift operands.
Superfluous trailing arguments	Fewer false-positive results.	This rule no longer flags calls to placeholder functions that trivially throw an exception.

The getName() predicate on functions and classes now gets a name inferred from the context if the function or class was not declared with a name.
The two-argument and three-argument variants of DataFlow::Configuration::isBarrier and TaintTracking::Configuration::isSanitizer have been deprecated. Overriding them no longer has any effect. Use isBarrierEdge and isSanitizerEdge instead.