Hyphens surrounded by non-breaking spaces are not texturized

[redsweater]

Thanks to Ticket #8161, a single hyphen or double hyphen surounded by space is converted to an en-dash or em-dash, respectively.

The problem is this conversion doesn't take place as expected when the space immediately before or after the affected hypehns is a non-breaking space.

Example paste the following into a post as HTML and view it in a browser after texturization:

Line 1&nbsp;-&nbsp;Non-breaking spaces around the hyphen.<br>
Line 2 - Regular spaces around the hyphen.<br>
Line 3&nbsp;- Non-breaking space before the hyphen.<br>
Line 4 --&nbsp;Non-breaking space after the double-hyphen.<br>
Line 5 -- Regular spaces around the double-hyphen.

Only the lines where "Regular spaces" are around the hyphens get converted as expected.Lines 1, 3, and 4 are not converted to match their regular-space counterparts.

It's reasonable to use non-breaking spaces in web content and I think that for situations where a non-breaking space is used it should imply the same kind of texturization for the hyphens as a regular space does.

The attached patch removes the static replacement rules for hyphens and adds dynamic rules to meet this expectation. I had to add a dynamic rule '--' to prevent it being prematurely converted in the static phase, when it was surrounded by appropriate spacing. Since I havd to move that one from static to dynamic, it made sense to me to just have all the hyphen-conversion behavior in one place in dynamic.