Factor out sequencing related things into an independant new library: "evoral".

Anything related to the storage of events/values over a range of time lives in evoral.
This includes MidiModel (Evoral::Sequence) and automation data (AutomationList (Evoral::ControlList),
	Automatable (Evoral::ControlSet), etc).
libs/evoral synced with http://svn.drobilla.net/lad/trunk/evoral r1511.


git-svn-id: svn://localhost/ardour2/branches/3.0@3754 d708f5d6-7413-0410-9779-e7cbd77b26cf

libs/evoral/test/sequence.cpp

@@ -0,0 +1,12 @@
+#include <evoral/Sequence.hpp>
+
+using namespace Evoral;
+
+int
+main()
+{
+	Glib::thread_init();
+
+	Sequence s(100);
+	return 0;
+}