eSpeak - added punctuation and capitals indications

[Jonathan Duddington]

I've added the ability to indicate punctuation and capital letters in
the text by either speaking their name, or by playing a sound.

I'm not sure whether what I've done is exactly what's wanted, so if
anyone wants to try it and let me know of suggestions for improvements,
please do so.

eSpeak text-to-speech is at:
   http://espeak.sourceforge.net

download the file:  test-1.09d-linux.zip

The ReadMe file inside gives the details.  It can speak either all
punctuation or just a specified set of punctuation characters.  It can
speak their names, or you can set up sound files (sound icons) to be
played instead.

Capital letters can be indicated by a sound, or by the word "capital",
or by raising the pitch of the capitalized word.

Also the feature of embedding commands within the text has been updated.

Questions which I'm unsure about:

1.  Should end-of-line be indicated?

2.  What about apostrophes within words. Currently these are not
indicated when speaking text since that would disrupt the pronunciation
of the word.

3.  The punctuation name is spoken in a slightly different tone from
the main text, to differentiate it.  Is that OK?

4.  The actual names for punctuation characters are defined in the
data/english_list file, so these can be changed if needed (then do
speak --compile).

5.  If the text is spoken at a fast rate, should the sound icons also
be shortened in duration?

6.  What is the best value for the pitch raise which indicates
capitals?  This is currently adjustable with the -k option to allow
experimentation.

7.  How should multiple capitals in a word be indicated?  Or a capital
which is not the first character of a word?  Or does that only need to
be considered when speaking letters individually (spelling)?

8.  Have I misunderstood the whole point of this, and punctuation and
capital indications are only needed when spelling out individual
characters?