Add AppVeyor pull request previews [ci skip]

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bc094bd.

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Add AppVeyor pull request previews

Merges #262
References #198

Add an AppVeyor continuous integration file to enable manuscript build previews in pull requests.
AppVeyorBot comments in pull requests with a link to the latest manuscript PDF.
Move shared continuous integration steps to an install script.
Change the continuous integration skip message in the deploy script to work across multiple continuous integration services.

README.md

@@ -1,7 +1,7 @@
 # Output directory containing the formatted manuscript
 
 The [`gh-pages`](https://github.com/manubot/rootstock/tree/gh-pages) branch hosts the contents of this directory at https://manubot.github.io/rootstock/.
-The permalink for this webpage version is https://manubot.github.io/rootstock/v/579547d8140dd01ddf652dfd4dbeb6c4a2c4b0eb/.
+The permalink for this webpage version is https://manubot.github.io/rootstock/v/bc094bd3d6cec6935298b4acf50e45ad55bf45c8/.
 To redirect to the permalink for the latest manuscript version at anytime, use the link https://manubot.github.io/rootstock/v/freeze/.
 
 ## Files
@@ -36,4 +36,4 @@ Verifying timestamps with the `ots verify` command requires running a local bitc
 ## Source
 
 The manuscripts in this directory were built from
-[`579547d8140dd01ddf652dfd4dbeb6c4a2c4b0eb`](https://github.com/manubot/rootstock/commit/579547d8140dd01ddf652dfd4dbeb6c4a2c4b0eb).
+[`bc094bd3d6cec6935298b4acf50e45ad55bf45c8`](https://github.com/manubot/rootstock/commit/bc094bd3d6cec6935298b4acf50e45ad55bf45c8).

index.html

@@ -6,7 +6,7 @@
  <meta name="viewport" content="width=device-width, initial-scale=1.0, user-scalable=yes" />
  <meta name="author" content="John Doe" />
  <meta name="author" content="Jane Roe" />
- <meta name="dcterms.date" content="2019-08-04" />
+ <meta name="dcterms.date" content="2019-08-09" />
  <meta name="keywords" content="markdown, publishing, manubot" />
  <title>Manuscript Title</title>
  <style>
@@ -86,7 +86,7 @@
 <header id="title-block-header">
 <h1 class="title">Manuscript Title</h1>
 </header>
-<p><small><em> This manuscript (<a href="https://manubot.github.io/rootstock/v/579547d8140dd01ddf652dfd4dbeb6c4a2c4b0eb/">permalink</a>) was automatically generated from <a href="https://github.com/manubot/rootstock/tree/579547d8140dd01ddf652dfd4dbeb6c4a2c4b0eb">manubot/rootstock@579547d</a> on August 4, 2019. </em></small></p>
+<p><small><em> This manuscript (<a href="https://manubot.github.io/rootstock/v/bc094bd3d6cec6935298b4acf50e45ad55bf45c8/">permalink</a>) was automatically generated from <a href="https://github.com/manubot/rootstock/tree/bc094bd3d6cec6935298b4acf50e45ad55bf45c8">manubot/rootstock@bc094bd</a> on August 9, 2019. </em></small></p>
 <h2 id="authors">Authors</h2>
 <ul>
 <li><p><strong>John Doe</strong><br> <img src="images/orcid.svg" alt="ORCID icon" class="inline_icon" /> <a href="https://orcid.org/XXXX-XXXX-XXXX-XXXX">XXXX-XXXX-XXXX-XXXX</a> · <img src="images/github.svg" alt="GitHub icon" class="inline_icon" /> <a href="https://github.com/johndoe">johndoe</a> · <img src="images/twitter.svg" alt="Twitter icon" class="inline_icon" /> <a href="https://twitter.com/johndoe">johndoe</a><br> <small> Department of Something, University of Whatever · Funded by Grant XXXXXXXX </small></p></li>