add timeout per package for PTS

- Motivation: PTS tests can run for long time and needs customized timeout.
- each method can declare timeout using @TimeoutReq(minutes=value)
  annotation.
- timeout is specified in minutes with 0 meaning no timeout.
- xml generator add timeout information like Class:method:10 if timeout
  annotation is present.
- CTS parses the xml and read timeout per each method, but the current
  architecture allows only one timeout for the whole package.
- Due to the restriction, the biggest timeout for the package is set.
- If timeout is not set, the current default of 10 mins will be used.
- The new annotation, TimeoutReq is defined in ctsutil.
  CTS tests can use it too. But it is ** strongly recommended to use this
  in a new package ** to prevent increasing test time too much.
- all file system tests and UI tests set to have timeout of 30 mins.

Change-Id: I9a19cb02b91376c581e13522d248872af8c7eee9