Pyvips

* fix with libvips nodeprecated [kleisauke]
* update README notes for py3.8+ on win [CristiFati]
* fix VipsObect.print_all() [jcupitt]
* add split, join, annotate animation examples [jcupitt]
* work around broken ffi bool type [amtsak]
* flag classes are now integer-valued so you can OR them [jcupitt]
* update docs for 8.15 [jcupitt]

* add seek and end handlers for TargetCustom [jcupitt]
* add `block_untrusted_set`, `operation_block_set` [jcupitt]
* update for libvips 8.13 [jcupitt]

* `repr()` will print matrix images as matrices [jcupitt]
* more robust bandwise index/slice; added fancy slicing (step != 1) [erdmann]
* fix `im.bandjoin([])`, now returns `im` [erdmann]
* add numpy-style extended indexing (index with list of ints or bools) [erdmann]
* earlier detection of unknown methods and class methods [jcupitt]
* add conversion from Image to numpy array via 'Image.__array__` [erdmann]
* add `Image.fromarray()` for conversion from numpy-ish arrays [erdmann]
* add `invalidate()` [jcupitt]
* add array-like functionality to `Image.new_from_array()` for conversion from
numpy-ish arrays [erdmann]
* add `Image.numpy()` (convenient for method chaining) [erdmann]
* add `tolist()` [erdmann]
* accept `pathlib.Path` objects for filenames (py3 only) [erdmann]
* cache pspec lookups for a 10% speed boost [jcupitt]

* fix logging of deprecated args [manthey]
* add shepards example [tourtiere]
* update docs for 8.12 [jcupitt]
* add pagesplit(), pagejoin(), get_page_height(), get_n_pages() [jcupitt]
* add atan2() [jcupitt]
* add `cache_get_max()`, `cache_get_max_mem()`, `cache_get_max_files()`,
`cache_get_size()` [hroskes]
* don't generate docs for deprecated arguments [jcupitt]
* buffer save tries with the target API first [jcupitt]
* add hyperbolic functions `sinh`, `cosh`, `tanh`, `asinh`, `acosh`,
`atanh` [jcupitt]
* add `values_for_flag` [kleisauke]

* better autodocs for enums [int-ua]
* better unreffing if operators fail [kleisauke]

* add `stdio.py` example
* update examples
* improve formatting of enum documentation
* regenerate docs
* remove old `vips_free` declaration, fixing API build on some platforms
[rajasagashe]