Add basic OSX AV capture plugin

Currently only cameras using interleaved 4:2:2 YCbCr are supported, e.g.
recent internal iSight cameras

plugins/mac-avcapture/CMakeLists.txt

@@ -0,0 +1,35 @@
+project(mac-avcapture)
+
+find_library(AVFOUNDATION AVFoundation)
+find_library(COREFOUNDATION CoreFoundation)
+find_library(COREMEDIA CoreMedia)
+find_library(COREVIDEO CoreVideo)
+
+
+include_directories(${AVFOUNDATION}
+                    ${COREFOUNDATION}
+                    ${COREMEDIA}
+                    ${COREVIDEO})
+
+set(mac-avcapture_HEADERS
+	)
+
+set(mac-avcapture_SOURCES
+	av-capture.m
+	plugin-main.c)
+
+set_source_files_properties(av-capture.m
+	PROPERTIES LANGUAGE C)
+	
+add_library(mac-avcapture MODULE
+	${mac-avcapture_SOURCES}
+	${mac-avcapture_HEADERS})
+
+target_link_libraries(mac-avcapture
+	libobs
+	${AVFOUNDATION}
+	${COREFOUNDATION}
+	${COREMEDIA}
+	${COREVIDEO})
+
+install_obs_plugin(mac-avcapture)