pidgin/nest

Unify contents of contributing section into a single page

2021-07-04, Sorvival
74890bc9a66d
Unify contents of contributing section into a single page

- Add some basic content to the index of the development section so that
it's not empty
- Remove contributing/mercurial page since its contents are now in the docs
page for using mercurial or in the (now single) contributing page.
- Add section in contributing page that points to useful link on how to
contribute code.
- Minor cleanups in the pre-existing contributing page
- Fix broken link in about index page that appeared after moving the
contributing section into a single page.

Testing Done:
Ran dev-server.sh and verified contents of the website looked as intended

Bugs closed: NEST-33

Reviewed at https://reviews.imfreedom.org/r/789/
<div class="download-now">
<a class="download-btn" href="/install/">
<span style="vertical-align: middle;">
<i class="fas fa-download dl-icon"></i> {{ T "Download" }} {{ .Site.Params.currentVersion | safeHTML }}
</span>
</a>
<b>Platforms:</b>
<a href="/install/#windows"><i class="fab fa-windows"></i></a>
<a href="/install/#macos"><i class="fab fa-apple"></i></a>
<a href="/install/#linux"><i class="fab fa-linux"></i></a>
<a href="/install/#freebsd"><i class="fab fa-freebsd"></i></a>
<a href="/install/#source"><i class="fas fa-code"></i></a>
</div>
<style>
.download-now {
display: block;
text-align: center;
width: 250px;
border-radius: 6px;
background-color: lightgrey;
margin: 0 auto;
}
.download-now .download-btn {
border-radius: 6px;
background-color: #8451a1;
color: white;
width: 100%;
padding: 15px;
font-size: large;
text-align: center;
display: block;
}
.download-now .download-btn:hover {
background-color: #322a38;
text-decoration: none !important;
}
.download-now .download-btn::after {
content: none !important;
}
.download-now .download-thing {
display: table-cell;
text-align: center;
vertical-align: middle;
}
.download-now .dl-icon {
display: inline-block;
vertical-align: middle;
}
.download-now .dl-text {
display: inline-block;
vertical-align: middle;
}
.download-now ul {
display: block;
list-style-type: disc;
margin-block-start: 0;
margin-block-end: 0;
margin-inline-start: 0;
margin-inline-end: 0;
padding-inline-start: 0;
}
.download-now a {
color: #8451a1;
}
</style>