HTML: Add option to not wrap collapsed tags, and bugfix

[andreyvolokitin]

See #1304

keep_collapsed_whitespace: true will keep any tag (TK_TAG_START or TK_TAG_SINGLE tokens) from wrapping on a new line if it has another tag (TK_TAG_END or TK_TAG_SINGLE tokens) as a direct previous sibling (that is, if TK_CONTENT between these tokens is empty). For the simplicity, in any other case/token sequence, this option will not take effect, including the following example:

<tag></tag>&nbsp;<tag></tag>

That is, this option won't take effect if TK_CONTENT is a string without whitespace. I am not sure if including this feature may be helpful or not, either way, it can be added later if required. Also, I did not take into account any handlebars content/tokens completely, though probably it would worth investigating, I think it may overcomplicate things...

I also made 2 bugfixes:

• record_tag(): tag should be trimmed, because sometimes it can contain whitespace (like tag\n)
• print_newline(): line_char_count should be reset to 0 only if wrapping is actually happening

[bitwiseman]

@andreyvolokitin - Take a look at the latest release.

[andreyvolokitin]

I ran tests from this PR on the latest release with unformatted: [] option, and also with no options, and these tests have failed

[bitwiseman]

Inline and the new html tokenizer superceeds this. Thanks for contributing. I hope you will do so again in the future.