get_the_tag_list should accept same arguments as get_the_category_list

[fireproofsocks]

It is bad form that the get_the_tag_list() relies on global variables to retrive tag information about a post. What if you want tag information about a post OTHER than the current post? The get_the_category_list() function is nearly identical in purpose, yet it does not suffer from this same restriction.

Compare the arguments here:
​http://codex.wordpress.org/Function_Reference/get_the_tag_list

To here:
​http://codex.wordpress.org/Function_Reference/get_the_category_list

I would expect these functions to have nearly identical inputs. If I am manually iterating over a list of post IDs (i.e. not in the loop), then it's a challenge to get the tag information here.

Add $id param

20072.2.diff​ also removes the default value for the $id parameter on some of the term functions. This parameter isn't optional as it's followed by the non-optional $taxonomy. Also fixes a notice when passing $id = 0 to get_the_terms() and global $post isn't an object.

Also see #17558 for $id = 0 stuff.

In [20549]:

Add $id parameter to get_the_tag_list() for consistency with get_the_(category|term)_list(). Props kawauso. Fixes #20072.

Also remove 'default' value of 0 for $id parameter in generic taxonomy functions
as it is a required parameter, and fix a notice when get_the_terms() is called
when $id = 0 and the $post global is not an object.