Add unittest

Add unittest
[   40s] + ./tinytemplate
[   40s]
[   40s] running 56 tests
[   40s] test compiler::test::test_comment ... ok
[   40s] test compiler::test::test_call ... ok
[   40s] test compiler::test::test_compile_literal ... ok
[   40s] test compiler::test::test_compile_value ... ok
[   40s] test compiler::test::test_compile_value_with_formatter ... ok
[   40s] test compiler::test::test_curly_brace_escaping ... ok
[   40s] test compiler::test::test_diallows_unknown_block_type ... ok
[   40s] test compiler::test::test_disallows_invalid_keywords ... ok
[   40s] test compiler::test::test_dotted_path ... ok
[   40s] test compiler::test::test_foreach ... ok
[   40s] test compiler::test::test_if_else_endif ... ok
[   40s] test compiler::test::test_if_endif ... ok
[   40s] test compiler::test::test_if_not_endif ... ok
[   40s] test compiler::test::test_indexed_path ... ok
[   40s] test compiler::test::test_mismatched_blocks ... ok
[   40s] test compiler::test::test_mixture ... ok
[   40s] test compiler::test::test_parse_error_line_column_num ... ok
[   41s] test compiler::test::test_parse_error_on_unclosed_if ... ok
[   41s] test compiler::test::test_parse_escaped_open_curly_brace ... ok
[   41s] test compiler::test::test_strip_whitespace_block ... ok
[   41s] test compiler::test::test_strip_whitespace_comment ... ok
[   41s] test compiler::test::test_strip_whitespace_followed_by_another_tag ... ok
[   41s] test compiler::test::test_strip_whitespace_value ... ok
[   41s] test compiler::test::test_with ... ok
[   41s] test compiler::test::test_unclosed_tags ... ok
[   41s] test template::test::test_escaping ... ok
[   41s] test template::test::test_for_loop ... ok
[   41s] test template::test::test_for_loop_first ... ok
[   41s] test template::test::test_call ... ok
[   41s] test template::test::test_for_loop_index ... ok
[   41s] test template::test::test_for_loop_last ... ok
[   41s] test template::test::test_formatter ... ok
[   41s] test template::test::test_if_else_taken ... ok
[   41s] test template::test::test_if_else_untaken ... ok
[   41s] test template::test::test_if_taken ... ok
[   41s] test template::test::test_if_untaken ... ok
[   41s] test template::test::test_ifnot_else_taken ... ok
[   41s] test template::test::test_ifnot_else_untaken ... ok
[   41s] test template::test::test_ifnot_taken ... ok
[   41s] test template::test::test_ifnot_untaken ... ok
[   41s] test template::test::test_indexed_paths ... ok
[   41s] test template::test::test_literal ... ok
[   41s] test template::test::test_indexed_paths_fall_back_to_string_lookup ... ok
[   41s] test template::test::test_nested_ifs ... ok
[   41s] test template::test::test_number_truthiness_one ... ok
[   41s] test template::test::test_number_truthiness_zero ... ok
[   41s] test template::test::test_path ... ok
[   41s] test template::test::test_root_branch ... ok
[   41s] test template::test::test_root_iterate ... ok
[   41s] test template::test::test_root_print ... ok
[   41s] test template::test::test_unescaped ... ok
[   41s] test template::test::test_unknown ... ok
[   41s] test template::test::test_value ... ok
[   41s] test template::test::test_whitespace_stripping_value ... ok
[   41s] test template::test::test_with ... ok
[   41s] test test::test_set_default_formatter ... ok
[   41s]
[   41s] test result: ok. 56 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out; finished in 0.07s