Add ability to generate ASCII documentation from the TeX files.

These changes add the ability to run 'make asterisk.txt' just like the existing
'make asterisk.pdf' commands to generate a text document from the TeX files we
have in the doc/tex/ directory. I've also updated a few of the .tex files because
they weren't properly escaping certain characters so they would show up as Unicode
characters (like [U+021C]). Made changes to the configure scripts so it would
detect the catdvi program which is required to convert the .dvi file generated
by latex.

I've also added a few lines to the build_tools/prep_tarball script so that the
text documentation gets generated and added to future tarballs of Asterisk
releases.

(closes issue #17220)
Reported by: lmadsen
Patches: 
      asterisk.txt.patch uploaded by lmadsen (license 10)
      asterisk.txt.patch-v4 uploaded by pabelanger (license 224)
Tested by: lmadsen, pabelanger

git-svn-id: http://svn.digium.com/svn/asterisk/trunk@258351 f38db490-d61c-443f-a65b-d21fe96a405b

1 files changed, 3 insertions, 1 deletions

diff --git a/doc/tex/localchannel.tex b/doc/tex/localchannel.tex
index 5c91eda2a..861697254 100644
--- a/doc/tex/localchannel.tex
+++ b/doc/tex/localchannel.tex
@@ -383,11 +383,13 @@ as expected.
 
 This following dialplan will not perform as expected.
 
+\begin{verbatim}
 [services]
 exten => 2,1,Dial(SIP/PHONE\_B,,L(60000:45000:15000))
 
 [internal]
-exten => 4,1,Dial(Local/2@services);
+exten => 4,1,Dial(Local/2@services)
+\end{verbatim}
 
 By default, the Local channel will try to optimize itself out of the call path.
 This means that once the Local channel has established the call between the