IExTypeInfo: better documentation of the interface semantics.

git-tfs-id: [http://falcon:8080/tfs/Projects]$/Phalanger/Main;C4302
PhpResourceManager debug assert fix

git-tfs-id: [http://falcon:8080/tfs/Projects]$/Phalanger/Main;C4303
aspnet_thru session handler
- <context>.$GLOBALS._SESSION listed properly in debugger

git-tfs-id: [http://falcon:8080/tfs/Projects]$/Phalanger/Main;C4345