Various documentation fixes.

Add some missing headers and ensure each header has a short description. doc.go
gets confused at declarations that break before the first (, so avoid doing
that. Also skip a/an/deprecated: in markupFirstWord and process pipe words in
the table of contents.

Change-Id: Ia08ec5ae8e496dd617e377e154eeea74f4abf435
Reviewed-on: https://boringssl-review.googlesource.com/2839
Reviewed-by: Adam Langley <agl@google.com>
diff --git a/include/openssl/base64.h b/include/openssl/base64.h
index 44f91eb..7aee990 100644
--- a/include/openssl/base64.h
+++ b/include/openssl/base64.h
@@ -99,8 +99,8 @@
 /* EVP_EncodeBlock encodes |src_len| bytes from |src| and writes the
  * result to |dst| with a trailing NUL. It returns the number of bytes
  * written, not including this trailing NUL. */
-OPENSSL_EXPORT size_t
-    EVP_EncodeBlock(uint8_t *dst, const uint8_t *src, size_t src_len);
+OPENSSL_EXPORT size_t EVP_EncodeBlock(uint8_t *dst, const uint8_t *src,
+                                      size_t src_len);
 
 /* EVP_EncodedLength sets |*out_len| to the number of bytes that will be needed
  * to call |EVP_EncodeBlock| on an input of length |len|. This includes the
@@ -158,6 +158,7 @@
 OPENSSL_EXPORT int EVP_DecodeBlock(uint8_t *dst, const uint8_t *src,
                                    size_t src_len);
 
+
 struct evp_encode_ctx_st {
   unsigned num;    /* number saved in a partial encode/decode */
   unsigned length; /* The length is either the output line length