FIXED, latex characters not escaped properly in nbconvert
FIX, don't use regex
update LATEX_SUBS table
put back a couple of regexp subs in escape_latex
update text_escape_latex
Escape latex fixes
Added ... to \ldots escape
Escape ansi like before
Revert "Escape latex fixes"

This reverts commit 69adeb152bd8b0f79bd8edcd6b90953b4928fa20.
This allows me to merge min's code to give him credit.
Merge pull request #3 from minrk/pr/3951

Update PR #3951
Better comment
remove sq brackets
Remove escape ansi
Fixed latex test to reflect removal of ansi strip
Revert "Better comment"

This reverts commit 0b94505a7acb2cf2292d054004fe8c439453ed0c.
Merge pull request #3951 from jdfreder/custom_verbate_esc_tex

nbconvert: fixed latex characters not escaped properly in nbconvert

use simple dict lookup process instead of sequential regular expressions that confuse each other.