[SP-811] Backport of PDI-10554

PDI-10554 - Setting num-mappers argument doesn't stay when switching from Command Line View to List View in Sqoop Import step (4.8)

fix the issue: java StreamTokenizer has special treatment for digits
make StreamTokenizer treat digits, dash and dot as "ordinary" characters

unit test: before the fix of PDI-10554 (SP-811) the unit test fails
Merge pull request #194 from mtseu/sp-811

[SP-811] - Backport of [PDI-10554] to 4.8