Squashed 'libmediaart/' changes from 2f0c497..c69fefb

1e32878 Release 0.5.0
ce504e0 build: Fixed distcheck issues
4e1aa78 build: Updated .gitignore to omit INSTALL, *.vapi...
fd73597 build: Updated configure.ac from autoscan suggestions
f868869 Merge branch 'api-cleanup'
23f3c73 extract: Fixed 'since' versions in documentation
880d09f libmediaart: Split API into  _process_buffer() and _process_file()
92cb3a3 docs: Fixed Makefile so we don't fail on distcheck with --enable-gtk-doc
733ce3f build: Improve warnings used when compiling
0d231f2 extract: Add _SYMLINK_FAILED error and report symlink() failure in get_heuristic()
adaa018 extract: Add GError for _NO_TITLE, which is required in some cases
91f827e tests: Don't expect media art extraction for NULL data buffer for !images
44c8e4a extract: Add GError * reporting right down to the plugins (pixbuf/qt)
0669d1e extract: Use a more logical ordered heuristic for caching strings
a3b64fe storage: Make g_message() calls g_debug() calls, output is unnecessary
1ba4e37 extract: Switch to initable MediaArtProcess object  from _init/_shutdown()
4e14f48 tests: Test for no error with media_art_process_file() with real use case
8f9056a extract: rename (private) media_art_heurstic and make args consistent with others
ce450d6 extract: Refactor media_art_process_file() to simplify the function
a1b2d8b extract: Allow error reporting with API using GError
aca5903 extract: Make GFile first parameter for _process_file()
6874977 tests: Removed unused function
f7317f8 extract: Fixed crash in QCoreApplication::applicationFilePath
f68fee1 extract: Save original filename
841d1c8 build: Require glib 2.38 for g_assert_true

git-subtree-dir: libmediaart
git-subtree-split: c69fefba7d3975deb1ef49b801d11bb0ef8d7b96
Merge commit '25cd8d8a19e2963f266e24886fbd0259f185406b'