Use `.hie` files for the Hyperlinker backend (#977)

# Summary

This is a large architectural change to the Hyperlinker.

  * extract link (and now also type) information from `.hie` instead
    of doing ad-hoc SYB traversals of the `RenamedSource`. Also
    adds a superb type-on-hover feature (#715).

 * re-engineer the lexer to avoid needless string conversions. By going
    directly through GHC's `P` monad and taking bytestring slices, we
    avoid a ton of allocation and have better handling of position
    pragmas and CPP.

In terms of performance, the Haddock side of things has gotten _much_
more efficient. Unfortunately, much of this is cancelled out by the
increased GHC workload for generating `.hie` files. For the full set of
boot libs (including `ghc`-the-library)

  * the sum of total time went down by 9-10% overall
  * the sum of total allocations went down by 6-7%

# Motivation

Haddock is moving towards working entirely over `.hi` and `.hie` files.
This change means we no longer need the `RenamedSource` from
`TypecheckedModule` (something which is _not_ in `.hi` files).

# Details

Along the way a bunch of things were fixed:

 * Cross package (and other) links are now more reliable (#496)
 * The lexer tries to recover from errors on every line (instead of at CPP
    boundaries)
 * `LINE`/`COLUMN` pragmas are taken into account
 * filter out zero length tokens before rendering
 * avoid recomputing the `ModuleName`-based `SrcMap`
 * remove the last use of `Documentation.Haddock.Utf8` (see  #998)
 * restructure temporary folder logic for `.hi`/`.hie` model

1 files changed, 42 insertions, 0 deletions

diff --git a/haddock-api/resources/html/solarized.css b/haddock-api/resources/html/solarized.css
index e83dc5ec..0146eedd 100644
--- a/haddock-api/resources/html/solarized.css
+++ b/haddock-api/resources/html/solarized.css
@@ -53,3 +53,45 @@ a:link, a:visited {
 a:hover, a.hover-highlight {
 	background-color: #eee8d5;
 }
+
+span.annot{
+    position:relative;
+    color:#000;
+    text-decoration:none
+  }
+
+span.annot:hover{z-index:25; background-color:#ff0}
+
+span.annot span.annottext{
+  display: none;
+  border-radius: 5px 5px;
+
+  -moz-border-radius: 5px;
+  -webkit-border-radius: 5px;
+
+  box-shadow: 5px 5px 5px rgba(0, 0, 0, 0.1);
+  -webkit-box-shadow: 5px 5px rgba(0, 0, 0, 0.1);
+  -moz-box-shadow: 5px 5px rgba(0, 0, 0, 0.1);
+
+  position: absolute;
+  left: 1em; top: 2em;
+  z-index: 99;
+  margin-left: 5;
+  background: #FFFFAA;
+  border: 2px solid #FFAD33;
+  padding: 0.8em 1em;
+}
+
+span.annot:hover span.annottext{
+  display:block;
+}
+
+/* This bridges the gap so you can mouse into the tooltip without it disappearing */
+span.annot span.annottext:before{
+  content: "";
+  position: absolute;
+  left: -1em; top: -1em;
+  background: #FFFFFF00;
+  z-index:-1;
+  padding: 2em 2em;
+}