preparing for the next release

[Masatake YAMATO]

Hi Luca,

I've just submmited bug fix patches.
(Please, ignore the patches which include line:

    Ready-to-Merge: yes)

These bug fix patches are applicable on

    [PATCH 01/25] ldv/unwind: improve stacktrace feature(v3)

which I submitted last year. 

ldv wrote:
> If the libunwind API used by this patch set is stable, then it makes sense.

All patches depends only on stable libunwind API.

Could you look at them?
I can send a full set of patches again. 
Tell me if they are convenient for you.

Masatake YAMATO