updated for version 7.3.1103
Problem:    New regexp engine: overhead in saving and restoring.
Solution:   Make saving and restoring list IDs faster.  Don't copy or check \z
	    subexpressions when they are not used.
Added tag v7-3-1103 for changeset 832bf8136d86
updated for version 7.3.1104
Problem:    New regexp engine does not handle "~".
Solution:   Add support for "~".
Added tag v7-3-1104 for changeset fc4d7f02ea3a
updated for version 7.3.1105
Problem:    New regexp engine: too much code in one function.  Dead code.
Solution:   Move the recursive nfa_regmatch call to a separate function.
	    Remove the dead code.
Added tag v7-3-1105 for changeset a804309e7327