[LANG-1586] refine StringUtils.wrap

[XenoAmess]

as title.

[coveralls]

Coverage decreased (-0.001%) to 94.956% when pulling 3746a2e on xenoamess-fork:refine_wrap into e233ab6 on apache:master.

[XenoAmess]

full jmh result at https://pastebin.ubuntu.com/p/9GTwkT5cgR/
in short:

StringUtilsWrapTest.test00New  avgt    5         6.636 ?      0.724  ns/op

StringUtilsWrapTest.test00Old  avgt    5         9.890 ?      4.562  ns/op

StringUtilsWrapTest.test01New  avgt    5         8.478 ?      0.679  ns/op

StringUtilsWrapTest.test01Old  avgt    5        15.321 ?      1.837  ns/op

StringUtilsWrapTest.test10New  avgt    5         8.493 ?      0.424  ns/op

StringUtilsWrapTest.test10Old  avgt    5        39.020 ?      2.662  ns/op

StringUtilsWrapTest.test11New  avgt    5         6.668 ?      0.400  ns/op

StringUtilsWrapTest.test11Old  avgt    5        33.370 ?      3.456  ns/op

StringUtilsWrapTest.test12New  avgt    5         2.360 ?      0.016  ns/op

StringUtilsWrapTest.test12ld   avgt    5         2.398 ?      0.155  ns/op

StringUtilsWrapTest.test20New  avgt    5         8.466 ?      0.498  ns/op

StringUtilsWrapTest.test20Old  avgt    5        30.567 ?      3.343  ns/op

StringUtilsWrapTest.test21New  avgt    5         6.435 ?      0.261  ns/op

StringUtilsWrapTest.test21Old  avgt    5        28.250 ?      5.174  ns/op

StringUtilsWrapTest.test22New  avgt    5         2.377 ?      0.109  ns/op

StringUtilsWrapTest.test22Old  avgt    5         2.380 ?      0.065  ns/op

StringUtilsWrapTest.testsNew   avgt    5  33745736.602 ?2654906.163  ns/op

StringUtilsWrapTest.testsOld   avgt    5  60026265.229 ?5142552.447  ns/op

indicates:
faster in any means. seems should merge.

[XenoAmess]

@garydgregory rebased. please find some time to review. thanks.