LaTeX: entries in general index are not styled like entries of domain indices

[jfbu]

Problem

Here for example from CPython 3.7 library.pdf (build using PR #5577 to workaround #5576 issue). The Python module index looks like this:

In contrast the general index looks like this

It doesn't use the same monospaced font, and extras in parentheses are not in italics.

Furthermore, there are problems with underscores for private methods, it would be better with monospace font as for literals.

The above build of CPython library.pdf uses xelatex and xindy, but it would be the same with pdflatex and makeindex.

Environment info

• OS: Mac
• Python version: 3.6.4
• Sphinx version: 1.8.1 + LaTeX: use lookbehind regex to not match semicolon at start #5577 patch for issue latex writer incorrectly handles indexing a sole semi-colon character #5576

[jfbu]

Fixed at 00a75b2 (refs: #5583)