Avoid re-initialization of time series for parent after child domain starts (#1953)

Avoid re-initialization of time series for parent after child domain starts (#1953)

This PR corrects an issue in which time series for a parent domain were re-initialized when a child domain started later than the initial time for a simulation.

TYPE: bug fix

KEYWORDS: time series, tslist, nest

SOURCE: Mathieu Landreau (LHEEA, Centrale Nantes, France), Michael Duda (NSF NCAR)

DESCRIPTION OF CHANGES:
Problem:
When running a simulation with a nest starting later than its parent and with the time series option activated, the parent domain time series is reinitialized when the nest starts.

Solution:
This issue is corrected by:

1) Initializing time series-specific members of the domain type, in particular, initializing `have_calculated_tslocs` to `.FALSE.`

2) Returning early from the wrf_tsin routine if `grid%have_calculated_tslocs` is `.TRUE.` (but avoiding changes to the value of `have_calculated_tslocs` otherwise).

ISSUE:
Fixes #1927

LIST OF MODIFIED FILES:
M frame/module_domain_type.F
M share/wrf_tsin.F

TESTS CONDUCTED:
- The problem was observed on a personal test case and the modifications fixed it.
- It passes Jenkins tests.

RELEASE NOTE: Fix an issue in which time series for a parent domain were re-initialized when a child domain started later than the initial time for a simulation.