Allow use options in TRIM() platform functions

[peter-gribanov]

Fix #275

Function TRUM() may have additional options and the specifications do not currently support them.

TRIM([LEADING | TRAILING | BOTH] ['trchar' FROM] str)

Using options

Spec::TRIM('field_name');
Spec::TRIM('field_name', Trim::TRAILING);
Spec::TRIM('field_name', Trim::LEADING, 'trchar');