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: https://origsvn.digium.com/svn/asterisk/trunk@258351 65c4cc65-6c06-0410-ace0-fbb531ad65f3

1 files changed, 3 insertions, 3 deletions

diff --git a/doc/tex/phoneprov.tex b/doc/tex/phoneprov.tex
index 04ca22fd0..790c1d7c2 100644
--- a/doc/tex/phoneprov.tex
+++ b/doc/tex/phoneprov.tex
@@ -79,7 +79,7 @@ subdirectory of AST\_DATA\_DIR/phoneprov specified.
 
 Since phone-specific config files generally have file names based on phone-specifc data, 
 dynamic filenames in res\_phoneprov can be defined with Asterisk dialplan function and 
-variable substitution. In the above example, \$\{TOLOWER(\$\{MAC\})\}.cfg $\Rightarrow$ 
+variable substitution. In the above example, \$\{TOLOWER(\$\{MAC\})\}.cfg =$>$
 000000000000.cfg would define a relative URI to be served that matches the format of 
 MACADDRESS.cfg, all lower case. A request for that file would then point to the template 
 found at AST\_DATA\_DIR/phoneprov/000000000000.cfg. The template can be followed by a 
@@ -96,8 +96,8 @@ Variable substitution on this value is done while building the route list, so
 dynamic filename.
 
 NOTE: Any dialplan function that is used for generation of dynamic file names MUST be 
-loaded before res\_phoneprov. Add "preload $\Rightarrow$ modulename.so" to 
-\path{modules.conf} for required functions. In the example above, "preload $\Rightarrow$ 
+loaded before res\_phoneprov. Add "preload =$>$ modulename.so" to 
+\path{modules.conf} for required functions. In the example above, "preload =$>$
 func\_strings.so" would be required.
 
 \section{Configuration of users.conf}