Show map 2.0

Show map v2.0 changes:

Added 'Show list' to Options page.

Show map v1.9 changes:

Updated markerclusterer code.

Show map v1.8 changes:

Updated phrases. Fixed URL link code. Updated template names and code.

Show map v1.7 changes:

Updated superglobal variable code.

Show map v1.6 changes:

Fixed issue where some threads were ignored.

Show map v1.5 changes:

Map page now has description of map in <title> tag.

Show map v1.4 changes:

Fixed issue with the Update function.

Show map v1.3 changes:

Added phrase to explain the purpose of the Update page.

Show map v1.2 changes:

Added code to help identify which thread has non-numeric view map bbcode.

Show map v1.1 changes:

Update link in the Show map admin page is now used to update the map. Maps are based on forums where each thread in that forum has a map bbcode in the first post.