add libical (#4657)

* add libical

* update formatting, remove doxygen from deps

* change spacing

packages/libical.rb

+require 'package'
+
+class Libical < Package
+  description 'An open source reference implementation of the icalendar data type and serialization format'
+  version '3.0.8.99' # 3.0.8 doesn't compile.
+  compatibility 'all'
+  source_url 'https://github.com/libical/libical/archive/07dc84fb0d5e50fb493005e10fa41930111da48f.zip'
+  source_sha256 '5fdf39b0ea654589bf2e9aa88ef1b0206c18aa6987f5a4299db3748e8b1eefd6'
+
+  depends_on 'glib'
+  depends_on 'icu4c'
+  depends_on 'gtk_doc' => ':build'
+  depends_on 'vala' => ':build'
+  depends_on 'gobject_introspection' => ':build'
+
+  def self.build
+    Dir.mkdir 'build'
+    Dir.chdir 'build' do
+      system "cmake #{CREW_CMAKE_OPTIONS} .. -G Ninja \
+        -DGOBJECT_INTROSPECTION=true \
+        -DICAL_GLIB_VAPI=true \
+        -DICAL_BUILD_DOCS=false \
+        -DLIBICAL_BUILD_TESTING=false"
+    end
+    system "ninja -C build"
+  end
+
+  def self.install
+    system "DESTDIR=#{CREW_DEST_DIR} ninja -C build install"
+  end
+end