Adds resource manager class. TRAC #12493 The resource manager class is now in charge of allocation & management of objects which may be shared by multiple contexts. Signed-off-by: Andrew Lewycky Signed-off-by: Nicolas Capens Signed-off-by: Daniel Koch Author: Shannon Woods git-svn-id: https://angleproject.googlecode.com/svn/trunk@360 736b8ea6-26fd-11df-bfd4-992fa37f6226