Add site config and index

Also fix string interpolation RFC to be compatible with Jekyll

docs/CNAME

@@ -0,0 +1 @@
+rfcs.luau-lang.org

docs/_config.yml

@@ -0,0 +1,5 @@
+name: Luau RFCs
+url: https://rfcs.luau-lang.org
+markdown: kramdown
+kramdown:
+  input: GFM

docs/index.md

@@ -0,0 +1,13 @@
+# RFCs
+
+{% assign sortedPages = site.pages | sort: 'title' %}
+
+<ul>
+{% for page in sortedPages %}
+{% assign ext = page.name | split:'.' | last %}
+{% if ext == 'md' and page.name != 'index.md' %}
+<li>
+<a href="{{ page.url }}">{{ page.title }}</a>
+</li>
+{% endif %}
+{% endfor %}

docs/syntax-string-interpolation.md

@@ -35,7 +35,9 @@ Because we care about backward compatibility, we need some new syntax in order t
    * `\` escapes `` ` ``, `{`, and itself `\`.
    * The pairs must be on the same line (unless a `\` escapes the newline) but expressions needn't be on the same line.
 2. An expression between the braces. This is the value that will be interpolated into the string.
+{% raw %}
    * Restriction: we explicitly reject `{{` as it is considered an attempt to escape and get a single `{` character at runtime.
+{% endraw %}
 3. Formatting specification may follow after the expression, delimited by an unambiguous character.
    * Restriction: the formatting specification must be constant at parse time.
    * In the absence of an explicit formatting specification, the `%*` token will be used.
@@ -98,11 +100,13 @@ print`Hello {name}`
 
 > Note: This restriction is likely temporary while we work through string interpolation DSLs, an ability to pass individual components of interpolated strings to a function.
 
+{% raw %}
 The restriction on `{{` exists solely for the people coming from languages e.g. C#, Rust, or Python which uses `{{` to escape and get the character `{` at runtime. We're also rejecting this at parse time too, since the proper way to escape it is `\{`, so:
 
 ```lua
 print(`{{1, 2, 3}} = {myCoolSet}`) -- parse error
 ```
+{% endraw %}
 
 If we did not apply this as a parse error, then the above would wind up printing as the following, which is obviously a gotcha we can and should avoid.