*: improve multiple things e.g. making some strings.cc functions modify strings in-place, improving m4_ax_have_qt.m4 code, making anime_db.cc rely on std::optional rather than std::shared_ptr (which was stupid anyway)

lib_LTLIBRARIES = libpugixml.la

libpugixml_la_SOURCES = \
	src/pugixml.cpp \
	src/pugiconfig.hpp

include_HEADERS = src/pugixml.hpp

libpugixml_la_CXXFLAGS = -std=c++11
ACLOCAL_AMFLAGS = -I m4