glcpp: Add test involving token pasting of INTEGER tokens.

glcpp: Add test involving token pasting of INTEGER tokens.

This test file is very similar to test 113-line-and-file-macros but uses token
pasting for cleaner quiz answers (without spaces between the digits). This
test passes thanks to the recent addition of support for pasting INTEGER
tokens, (but would have failed without that).

(Note that this test is distinct from test 059-token-pasting-integer which
pastes integers parsed from the source. Those are parsed to INTEGER_STRING
tokens and are already pasted correctly as verified by that test. The only way
to generate the INTEGER tokens which currently fail to paste is with an
internal define such as __LINE__ that results in an integer.)

Reviewed-by: Matt Turner <mattst88@gmail.com>