IBus 1.5.15 is released

[Takao Fujiwara]

ibus 1.5.15 is released:
https://github.com/ibus/ibus/releases/tag/1.5.15

The link is the demo of emoji typing:
https://youtu.be/MUgP0oWltbY

* Fix GVariant leaks (Eric R. Schulz) 997e5cb
* ui/gtk3: Fix radio buttons on Property Panel ceb6a9b
Update translations 708e5e5
* Fix warning messages during panel resizes af66ace
* src: Hide lookup table if emoji annotation does not hit e795eda
* src: Enable to type digit to commit emoji on lookup window 4d86e59
* src: Enable PageUp, PageDown, CandidateClick buttons with emoji lookup faf5e3c
* ui/gtk3: support scroll event in candidates panel (Peng Wu) 52b7272
* src: Avoid emoji typing during Unicode typing f80dcc9
* ui/gtk3: Fix panel CSS format for GTK 3.22 aacf5ad
* util/IMdkit: Fix the range of memset() in i18nIc.c 371535b
* ui/gtk3: Refactor color of a selected candidate on lookup window bdc83bc
* ui/gtk3: Free normal_color in CandidateArea b8f5553
* ui/gtk3: Refactor to set panel icon b498ff5
* ui/gtk3: Fix typo in switcher.get_input_context_path() fcb90f7
* bus: fix service file when --disable-xim is specified (Marc-Antoine
Perennou) 993289f
* Fix memory leak in IBus.Bus.get_global_engine() (Eric R. Schulz) 0a24481
* Move emoji implementation from IBusEngineSimple to IBusPanel 02d99aa
* setup: Set emoji preview text on font setting 13bf503
* Add 'ibus emoji' command for no ibus panel desktops c37989a
* Release 1.5.15 f7f3bc8
* Fix a build failure with --disable-emoji-dict 641c3cb

You can get `emoji.json` with `npm install -g emojione` or Fedora
provides `nodejs-emojione-json` package.
You can get emoji annotation files from
https://github.com/fujiwarat/cldr-emoji-annotation or Fedora provides
`cldr-emoji-annotation` package.
If you run './configure --disable-emoji-dict', you need to delete
tools/main.c and `make` will create it again from tools/main.vala -
`make -C tools maintainer-clean-generic' can delete tools/main.c