add cl_abap_regex/cl_abap_matcher

[larshp]

possible workaround: use FIND REGEX

[larshp]

need RESULTS, abaplint/transpiler#147

DATA lo_regex TYPE REF TO cl_abap_regex.
DATA lo_matcher TYPE REF TO cl_abap_matcher.
DATA lt_result TYPE match_result_tab.

CREATE OBJECT lo_regex
  EXPORTING
    pattern     = 'aa'
    ignore_case = abap_true.

lo_matcher = lo_regex->create_matcher( text = 'fooaabar' ).
lt_result = lo_matcher->find_all( ).