Fix uninitialized fields

The memory sanitizer would complain:

==4157154==WARNING: MemorySanitizer: use-of-uninitialized-value
    #0 0x7fc191d0a85b in TranslateWord3 /home/samy/brl/speech/espeak-ng-git/src/libespeak-ng/translate.c:1065:7
    #1 0x7fc191d02916 in TranslateWord /home/samy/brl/speech/espeak-ng-git/src/libespeak-ng/translate.c:1100:14
    #2 0x7fc191d1b324 in TranslateWord2 /home/samy/brl/speech/espeak-ng-git/src/libespeak-ng/translate.c:1448:15
    #3 0x7fc191d14ebc in TranslateClause /home/samy/brl/speech/espeak-ng-git/src/libespeak-ng/translate.c:2623:17
    #4 0x7fc191cfbc9b in SpeakNextClause /home/samy/brl/speech/espeak-ng-git/src/libespeak-ng/synthesize.c:1569:2
    #5 0x7fc191cd52fc in Synthesize /home/samy/brl/speech/espeak-ng-git/src/libespeak-ng/speech.c:457:2
    #6 0x7fc191cd6d7c in sync_espeak_Synth /home/samy/brl/speech/espeak-ng-git/src/libespeak-ng/speech.c:570:29
    #7 0x7fc191cd6d7c in espeak_ng_Synthesize /home/samy/brl/speech/espeak-ng-git/src/libespeak-ng/speech.c:678:10
    #8 0x7fc191ca0340 in espeak_Synth /home/samy/brl/speech/espeak-ng-git/src/libespeak-ng/espeak_api.c:90:32
    #9 0x4a4381 in main /home/samy/brl/speech/espeak-ng-git/src/espeak-ng.c:691:3
    #10 0x7fc19168b7fc in __libc_start_main csu/../csu/libc-start.c:332:16
    #11 0x421449 in _start (/home/samy/ens/projet/1/speech/espeak-ng-git/src/.libs/espeak-ng+0x421449)

  Uninitialized value was created by a heap allocation
    #0 0x45000d in malloc (/home/samy/ens/projet/1/speech/espeak-ng-git/src/.libs/espeak-ng+0x45000d)
    #1 0x7fc191d1ca29 in NewTranslator /home/samy/brl/speech/espeak-ng-git/src/libespeak-ng/tr_languages.c:242:26
    #2 0x7fc191d1ca29 in SelectTranslator /home/samy/brl/speech/espeak-ng-git/src/libespeak-ng/tr_languages.c:482:7

(and similar for expect_verb_sn expect_noun, expect_past,
clause_upper_count, clause_lower_count)

Indeed TranslateWord3 doesn't always initialize these fields. Better
just initialize them directly from the Translator creation.

src/libespeak-ng/tr_languages.c

 	tr->transpose_map = transpose_map_latin;
 	tr->frequent_pairs = NULL;
 
+	tr->expect_verb = 0;
+	tr->expect_past = 0;
+	tr->expect_verb_s = 0;
+	tr->expect_noun = 0;
+
+	tr->clause_upper_count = 0;
+	tr->clause_lower_count = 0;
+
 	// only need lower case
 	tr->letter_bits_offset = 0;
 	memset(tr->letter_bits, 0, sizeof(tr->letter_bits));