build(PKGBUILD): add PKGBUILD for AUR

dist/aur/PKGBUILD

+# Maintainer: TheBitStick <thebitstick@tfwno.gf>
+pkgname=journable-git
+_pkgname=journable
+pkgver=0.1.1.r1.4957fc5
+pkgrel=1
+pkgdesc="A simple bullet journal."
+arch=(any)
+url="https://gitlab.gnome.org/BjoernDaase/journable"
+license=('GPL3')
+depends=('gtk3' 'appstream-glib' 'python')
+makedepends=('git' 'meson' 'cmake')
+checkdepends=()
+optdepends=()
+provides=(${pkgname%-git})
+conflicts=(${pkgname%-git})
+backup=()
+options=()
+source=("git+${url}.git")
+md5sums=('SKIP')
+
+pkgver() {
+	cd ${_pkgname}
+	git describe --long --tags | sed 's/^v//;s/\([^-]*-\)g/r\1/;s/-/./g'
+}
+
+build() {
+	meson --prefix=/usr --buildtype=plain journable build
+	ninja -C build
+}
+
+package() {
+	DESTDIR="$pkgdir" ninja -C build install
+}