Add question regarding storage removal for empty vectors in README

Author: tothambrus11

readme.md

@@ -9,6 +9,7 @@
 - Should we ever shrink vectors?
 - Should we have size and capacity inline or in the storage header?
 - Should we have a small inline buffer for a couple of elements?
+- When storing the size and capacity out of line, should we always remove the storage iff the vector is empty so that `empty()` checks can be a simple nullptr check for the storage without the need for dereferencing the out of line buffer?
 
 Implement basis operations, provide the rest through concept extensions