Log Message:
glibmm: update to 2.54.1.

2.54.1 (stable):

Glib:
* Variant: Don't use std::index_sequence from C++14.
  (Kjell Ahlstedt, Jonathan Wakely) Bug #787648 (Armin K.)

Documentation:
* Note that Gio::Application::property_resource_base_path() shall not
  be used. It has a bug that's hard to fix without breaking ABI.
  (Kjell Ahlstedt) Bug #787496 (Daniel Boles)

gmmproc:
* Convert all property documentation to C++.
  (Kjell Ahlstedt) Bug #787698 (Daniel Boles)

2.54.0 (stable):

Glib:
* Added DBusObjectPathString and DBusSignatureString, for Variants with D-Bus \ 
object paths or D-Bus signatures,
  and add Variant specializations for Variant<Glib::DBusObjectPathString>,
  Variant<Glib::DBusSignatureString> and \ 
Variant<std::vector<Glib::DBusObjectPathString>>.
  (Kjell Ahlstedt) Bug #785700
* Variant: Add template specialization for std::tuple.
  (Alexander Rössler) Bug #777791

Gio:
* ActionGroup: Add optional action_name parameters to some signals.
  (Kjell Ahlstedt)
* Settings: Add optional key parameter to the writable_changed signal.
  (Kjell Ahlstedt)

gmmproc:
* Write signal flags to generated documentation
  (Kjell Ahlstedt) Bug #785895 (Daniel Boles)
* Write default values of properties to generated documentation
  (Kjell Ahlstedt) Bug #785895 (Daniel Boles)
* Warn for unmatched deprecations in signals and properties.
  (Kjell Ahlstedt)
* Accept curly braces in default values in _WRAP macros.
  (Kjell Ahlstedt) Bug #783216 comment #13 (Daniel Boles)
* Fix _WRAP_ENUM for enumerators with apostrophes.
  (Kjell Ahlstedt)
* Add new elements types for the docs_override:
  substitute_type_name and substitute_enumerator_name.
  (Kjell Ahlstedt) Bug #86864

2.52.1 (stable):

Gio:
* TlsDatabase: Fix memory leak in a vfunc.
  (Kjell Ahlstedt) Bug #783360

Documentation:
* Update docs of get_*_name().
  (Daniel Boles)

Build:
* MacOS: Really correct build without gdesktopinfo.
  (Kjell Ahlstedt) Bug #781947

2.52.0 (stable):

Gio:
* UnixSocketAddress::create(): Remove the default value for the type
  parameter to avoid ambiguity.
  (Kjell Ahlstedt) Bug #782592

Gio::DBus
* Proxy: Wrap call() and call_sync() methods.
  (Vyacheslav Yurkov) Bug #781818

Documentation:
* RefPtr: Clarify comment about undefined behaviour.
  (Daniel Boles)

2.51.7 (unstable):

Glib:
* SettingsSchemaKey: Add missing value/range methods.
  (Daniel Boles) Bug #774903
* Variant: Replace throw(std::bad_cast) with noexcept(false),
  to fix the build with C++17.
  See https://bugzilla.redhat.com/show_bug.cgi?id=1438766
  (Murray Cumming)
* VariantType: Deprecate first() and next(). Add get_item_types()
  (Kjell Ahlstedt) Bug #775741

Gio:
* ActionMap: Add add_action_with_parameter() that takes a parameter type,
  and deprecated the existing method, because it cannot work.
  (Daniel Boles) Bug #774444
* SimpleAction: Make set_state() public.
  (Daniel Boles) Bug #777953

Build:
* MacOS: Correct build without gdesktopinfo.
  (John Ralls) Bug #781947
* Glib::Object: Suppress deprecation warning for g_object_newv() with glib 2.54.
  (Kjell Ahlstedt)

2.51.6 (unstable):

This is version 2.51.6 of glibmm-2.24. Ignore versions 2.51.1 to 2.51.5 of
unstable glibmm-2.52. Unstable glibmm-2.52 is now unstable glibmm-2.54,
leaving the 2.51/52 version numbers again for use by stable glibmm-2.52.

Glib:
* Dispatcher:
  - autodeduce the type of the fd field.
  (Marcin Kolny) Bug #772074
  - Don't cast a HANDLE to an int on Windows.
  (Kjell Ahlstedt) Bug #772074
* ustring: Add cbegin() and cend().
  (Murray Cumming)

Gio:
* Action: Include variant.h in the heaer.
  (Daniel Boles) Bug #777953
* Application: get_default(): Correct the reference counting.
  (Kjell Ahlstedt) Bug #779936
* Settings:
  - Really add set_enum() and set_flags().
  (djb) Bug #774647
  - Writable-change-event signal: Correct the type of the key parameter.
  (Marcin Kolny) Bug #773977
* SettingsSchemaSource: get_default(): Correct the refcounting.
  (Marcin Kolny) Bug #774593

Gio::DBus:
* Proxy: Fix memory leak in get_cached_property_names().
  (Kjell Ahlstedt) Bug #775210

Documentation:
* Glib::Variant: Improve documentation of maybe types.
  (Daniel Boles) Bug #778219
* Gio::ActionMap: Clarify doc of ActivateWithParameterSlot
  (Daniel Boles)

Build:
* Visual Studio builds: "Install" the .pdb files
  (Chun-wei Fan)