strbuf.h: drop asciidoc list formatting from API docs

Using a hanging indent is much more readable. This means we
won't format as asciidoc anymore, but since we don't have a
working system for extracting these comments anyway, it's
probably more important to just make the source readable.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

strbuf.h

@@ -13,26 +13,26 @@
  *
  * strbufs have some invariants that are very important to keep in mind:
  *
- * . The `buf` member is never NULL, so it can be used in any usual C
+ *  - The `buf` member is never NULL, so it can be used in any usual C
  *    string operations safely. strbuf's _have_ to be initialized either by
  *    `strbuf_init()` or by `= STRBUF_INIT` before the invariants, though.
- * +
+ *
  *    Do *not* assume anything on what `buf` really is (e.g. if it is
  *    allocated memory or not), use `strbuf_detach()` to unwrap a memory
  *    buffer from its strbuf shell in a safe way. That is the sole supported
  *    way. This will give you a malloced buffer that you can later `free()`.
- * +
+ *
  *    However, it is totally safe to modify anything in the string pointed by
  *    the `buf` member, between the indices `0` and `len-1` (inclusive).
  *
- * . The `buf` member is a byte array that has at least `len + 1` bytes
+ *  - The `buf` member is a byte array that has at least `len + 1` bytes
  *    allocated. The extra byte is used to store a `'\0'`, allowing the
  *    `buf` member to be a valid C-string. Every strbuf function ensure this
  *    invariant is preserved.
- * +
+ *
  *    NOTE: It is OK to "play" with the buffer directly if you work it this
  *    way:
- * +
+ *
  *    ----
  *    strbuf_grow(sb, SOME_SIZE); <1>
  *    strbuf_setlen(sb, sb->len + SOME_OTHER_SIZE);
@@ -40,17 +40,17 @@
  *    <1> Here, the memory array starting at `sb->buf`, and of length
  *    `strbuf_avail(sb)` is all yours, and you can be sure that
  *    `strbuf_avail(sb)` is at least `SOME_SIZE`.
- * +
+ *
  *    NOTE: `SOME_OTHER_SIZE` must be smaller or equal to `strbuf_avail(sb)`.
- * +
+ *
  *    Doing so is safe, though if it has to be done in many places, adding the
  *    missing API to the strbuf module is the way to go.
- * +
+ *
  *    WARNING: Do _not_ assume that the area that is yours is of size `alloc
  *    - 1` even if it's true in the current implementation. Alloc is somehow a
  *    "private" member that should not be messed with. Use `strbuf_avail()`
  *    instead.
- */
+*/
 
 /**
  * Data Structures