Add copyright notice to our appdata file

See
http://blogs.gnome.org/hughsie/2013/10/01/copyright-in-appdata-files/
(cherry picked from commit 770d64aa32eb36aba729c96c4501e83fe43b41f7)
Update screenshots in apddata file
(cherry picked from commit 5450f962e8c169084abcbc9870b76514e0785758)
Announce changes to appdata format on devel list
(cherry picked from commit 8347285e7f837cb9d6a9880d4ec1a177b535de51)
Delete Sony thumbnail data
(cherry picked from commit 4d3fa6690204251e6aa8a3afd34a7c1982b7affa)
wb_presets: Sony NEX-6 == Sony NEX-5R
(cherry picked from commit eba90b6b31f7ca593120890eb9fe9a123e8b3f63)
wb_presets: Sony NEX-6 copy notice
(cherry picked from commit c927d1bad2752654979517e09b2c8e20a976ccb4)
rawspeed: import svn r600
(cherry picked from commit ab69db9afa89c17c10d82bb41af715c4147435b9)
rawspeed: preliminary Nikon P7800 support
(cherry picked from commit b40450c1afa8a01d3be66a7fa867f981d580fc70)
rawspeed: preliminary Sony NEX-5T support
(cherry picked from commit 930dd9003354eac925229a47db15b485912aaa23)
adobe_coeff: preliminary Sony NEX-5T matrix
(cherry picked from commit 2ac4d20c0f7092eb06828c75a7327a1f9d580a98)
adobe_coeff: very experimental Nikon P7800 matrix
(cherry picked from commit 2a684143f833ce59301709b477ca9737cbdb6d63)
strdup locale to avoid use-after-free

To be sure you can use the returned string encoding the currently selected locale at a later time, you must make a copy of the string. It is not guaranteed that the returned pointer remains valid over time.
From https://www.gnu.org/software/libc/manual/html_node/Setting-the-Locale.html
(cherry picked from commit bc7d5ac610b3662e3e05df0a071bd4871dd295af)
gtk: fixed typo.
(cherry picked from commit 790f8c901e62f7a4f11c072227a46d613c7d1c5f)
sraw: use correct pitch when loading buffer.
(cherry picked from commit 43d06f25bd2a251cf89e5b2cfaeeb558a59cb129)
rawspeed: update to svn r603
(cherry picked from commit 8388525adc9e8f7f9f2c18c4c9f5eef0aafae16e)
rawspeed: Canon EOS 50D whitepoint fixes
(cherry picked from commit 6e01465f5e328eb8fbb7bf1c663afba0f540de7c)
wb_presets: Adding support for several Pentax cameras
(cherry picked from commit ec6f14db984e8a645cd7db7e1f7a4eaa8d0e38ab)
wb_presets: Adding whitebalance presets for "Canon EOS-1D X" and "Canon EOS 70D"
(cherry picked from commit 54d5158a9f4379f61708fa719ba6d736aa78e2c8)