dateTime was ignoring specified local_or_utc value

[TranscendOfSypherus]

Line 1210: always assumed the provided time_t was in local time.

thus the following output:

Timezone localTz;
localTz.setLocation("Australia/Melbourne");

// -- works for TIME_NOW as it gets hydrated in local time
Serial.println("Current Time: ");
Serial.print("         UTC: "); Serial.println(UTC.dateTime());
Serial.print("       Local: "); Serial.println(localTz.dateTime());
Serial.println();

// Current Time:
//          UTC: Saturday, 03-Aug-2019 03:56:27 UTC
//        Local: Saturday, 03-Aug-2019 13:56:27 AEST

time_t testTime = 1564953937;
Serial.println("    Simulate: ");
Serial.print("       Local: "); Serial.println(localTz.dateTime(testDate));
Serial.print("       Local: "); Serial.println(localTz.dateTime(testDate, LOCAL_TIME));
Serial.print("       Local: "); Serial.println(localTz.dateTime(testDate, UTC_TIME));

//  Simulate:
//       UTC: Sunday, 04-Aug-2019 21:25:37 UTC
//     Local: Sunday, 04-Aug-2019 11:25:37 AEST
//     Local: Sunday, 04-Aug-2019 11:25:37 AEST
//     Local: Sunday, 04-Aug-2019 11:25:37 AEST <--- wrong

with this PR:

// Current Time:
//          UTC: Saturday, 03-Aug-2019 03:56:27 UTC
//        Local: Saturday, 03-Aug-2019 13:56:27 AEST
//
//  Simulate:
//       UTC: Sunday, 04-Aug-2019 21:25:37 UTC
//     Local: Sunday, 04-Aug-2019 11:25:37 AEST
//     Local: Sunday, 04-Aug-2019 11:25:37 AEST
//     Local: Monday, 05-Aug-2019 07:25:37 AEST <--- correct

[Scratchydisk]

Thanks Transend... I can confirm this addresses an issue I was having when converting UTC to BST.