soft `з, с` if previous syllable is soft

fix "здж" > "ждж" rule, fix test for it
add rules for "б г д дз дж з" at the end of words
add devoiced rules conversion
add some words to vocabulary
added tests for new rules

nvda happened to be speaking 3647 because strtoi was actually
overflowing. Better make sure to have proper ascii to number translation
before continuing.

Fixes #1385

cover all phoneme rules with
the tests.

added tests to:
- language-numbers-cardinal.test
- tests/language-phonemes.test
- tests/language-pronunciation.test

./src/espeak-ng -v ar --path=$PWD 5777

would access out of the vowel_stress array, because GetVowelStress, in the
phcode == phonSYLLABIC case, only increments count if stress is 0.  This
code seems fishy, and is not coherent with the loop in SetWordStress.  I
made it similar to the other case above, thus fixing the out-of-bound
access.

This is modifiying the stress in the tn test, I don't know whether this
is expected.