Add way to install MathJax to a particular profile
Make profile not set a default
Made profile the default install option, install_dir the explicit
simplify join
help_end transformer shouldn't pick up ? in multiline string

Closes gh-4134
Quote notebook install

ZSH needs the quotes to treat the argument properly
Select default title when renaming a notebook

The default notebook name is Untitled<x>. It is unlikely the user will want to
keep this name or part of it. Instead, select the text in the input field so the
user can easily type over the name and change it.
Add feature description to whatsnew
Merge pull request #4144 from takluyver/i4134

help_end transformer shouldn't pick up ? in multiline string

The help_end() transformer was already tokenizing the line to determine whether the ? was in a comment, so I just extended this to check for multi-line strings as well.

Closes #4134
Merge pull request #4160 from kevinburke/quote-readme

Add quotes around ".[notebook]" in readme
Merge pull request #4161 from kevinburke/select

Select name when renaming a notebook
Merge pull request #4104 from rgbkrk/mathjax_profile

Add way to install MathJax to a particular profile
remove special handling of speaker notes
clarify `reveal-prefix` alias name
update nbconvert docs about reveal.js
add proxying tornado server in Serve post-processor
use local reveal.js url prefix by default

CDN redirect is handled by the Serve post-processor if necessary
protect against unavailable tornado in post_processors.init
update reveal docs with recent changes
add nbconvert serve exclusions without tornado