test script was improved.

test script was improved.

* tests/lha-test.in: added an optional numeric command-line argument, and a command-line switch -n.
when the numeric argument is specified, only the testsuite is performed.
and the -n switch is specified, it is not made cleanup trash files which is result of the test.

* tests/lha-test11: On MS-Windows, should consider the length of current path.

* tests/lha-test11: On MS-Windows, if current directory is too deep, skip this test.

git-svn-id: svn+ssh://svn.sourceforge.jp/svnroot/lha/lha/trunk@871 6a8cc165-1e22-0410-a132-eb4e3f353aba