Update libgltf: new build system and various fixes

Building:
- The new tarball has reasonable build system so
build libgltf as external package instead of compiling
source files directly.
- Freetype dependancy is removed

Improvements comes with the new libgltf
- Can rotate the models too (orbit mode)
- Two camera handling mode: walkthrough and orbit
(press M to change).
- gltf_animation_set_time() works
- FPS can be displayed without freetype (press F)

Additional notes:
- There were some bugs/regressions which are fixed
during the integration (see patches).
- License files are uddated now.
- libgltf building is enabled only on those platforms
on which gltf support actually works (windows and linux)

Reviewed-on: https://gerrit.libreoffice.org/9895
Reviewed-by: Zolnai Tamás <zolnaitamas2000@gmail.com>
Tested-by: Zolnai Tamás <zolnaitamas2000@gmail.com>
(cherry picked from commit 6403f2b59b4c83e0899012e5ca0ddd705784350c)

Conflicts:
	avmedia/source/opengl/oglplayer.cxx

Change-Id: Ia6c9c4da53a9b4fedba0d73aa5791489f8ad424b

libgltf: variable names need module prefix

Change-Id: Id144a483fe5576cdd546ac5da87890dc61f964b3
(cherry picked from commit d83e66da94d9c789190c4729c8f0c8464e99ba88)

libgltf: add patch to find the headers in WORKDIR

Change-Id: I8570511be7c1d6de94ee82e18bad5b00b36d99bb
(cherry picked from commit dfe787ef5de1b38e61989507b26ee4b92f25b9d5)

libgltf: try to fix the MSVC2010 build

Change-Id: I8dde439d19be45d5039904b6e917b17ca0ee4758
(cherry picked from commit 96ff10449464ae9d869fe21dccf193a6eef670c1)

glTF rendering: moving in walktrough mode is to fast

Change-Id: I2b7869c6c14b69732db864a03a2d9b6638424cf7
(cherry picked from commit f2b5ece0caca18f21f7c8e42a84d451bb399ec35)

libgltf: use --with-pick

Change-Id: Ide01491460c9c81ed044be762c7dd07e8a5ca575
(cherry picked from commit bb9078e3dee48afc4c2bd8006a892924f8b38b39)

libgltf: replace configure patch to avoid using autoreconf

Change-Id: Idcab012af9c27c4fed31c07ce230816d1c61d605
(cherry picked from commit c5bb272883e042e38c58847f6eb2a2f94c6ef919)

libgltf: try again with this configure patch

Touch only the configure but not the configure.ac

Change-Id: Iee93036f2378f29530ffae9be8b4324e8425d2ec
(cherry picked from commit 211e07c0e02ebfe9cea4b5d97b614a23f8b2012c)

libgltf: remove dependencies of config.h.in

It seems something is wrong with the files in the
libgltf tarball (maybe wrong timestamps?), because
config.h.in is always regenerated by make (autoheader).
It causes build problems so just remove the deps for this time.

Change-Id: I404c29673987d7c8f75ec8fe4978173593c75a2f
(cherry picked from commit 3bebda9cd3269d684a3b430e25f17951deaf3d3d)

libgltf: fix typo in license

Change-Id: I0e5f3afb19c2457c5ccca922e75e617312801ab9
(cherry picked from commit 1d5e875a6c61ddc9fbf0ed09878b7dfb75f89fe3)

libgltf: compiler error fixes: missing include and missing namespace

Thanks to Rene Engelhard for the report and the fixes.

Change-Id: Ia14980bdbcd9e714b1e9cd41f04af9371aa22371
(cherry picked from commit 481a17b6a6fb332935c3e41c077cc5f60b751021)

libgltf: it seems gb_SPACE is not that we need here

Change-Id: I099f2bb007cdd29db25a99ca84e53115a12379bd
(cherry picked from commit c7d6541f5daa59d04accb30c727a83d936f02150)

libgltf: fix wrong include path to config_$(gb_Side)

Change-Id: I63d1822fd08c997a9432ed09ada6d5299bc658b1
(cherry picked from commit ab028bf00e3e5f8424ea5e746815e8438144e4bf)

libgltf: use WHITESPACE

Change-Id: I47ca82d5f08431c8af8b8a85cfbfd083ebd6fda0
(cherry picked from commit b05b970daaf69b5b491b847375ee07539de9481f)

libgltf: make 'Requires' valid in libgltf-0.0.pc file

Thanks to Rene Engelhard for help to make it valid.

Plus glu is not used, so remove it.

Change-Id: I5e3631e9b3d24c2b1d9044192d7c0a55c234f7c0
(cherry picked from commit 4bdbc1c93bb3b7e6b1f2fc9a700977ccfa3daae4)

Change-Id: Ia14980bdbcd9e714b1e9cd41f04af9371aa22371
Reviewed-on: https://gerrit.libreoffice.org/9922
Reviewed-by: Miklos Vajna <vmiklos@collabora.co.uk>
Tested-by: Miklos Vajna <vmiklos@collabora.co.uk>