Attempt to build a regex from an empty list failed when calling new RegEx('[]', 'ig') on IE 6/7/8.
Now allowing null for the object, and also not trying to create the regex even if we have an empty object just in case.
Fixes Bug 8028, Bug 8115, Bug 15406, Bug 17141, Bug 8732
1. Sites can specify custom collations.
The script accepts an object "tableSorterCollation" which contains a lookup
table, how specific characters should be treated.
For example, after setting "tableSorterCollation={'ä':'ae', 'ß':'ss'};" in the
site's common.js any string containing an ä or Ä will be sorted as if it were a
'ae'.
2. Table rows can be forced to use a specific data type.
By setting class="sort-{Parsername}", the row will be parsed with the specified
algorithm. class="sort-date" would force date sorting etc.
The following parsers are available: text, IPAddress, number, url, currency,
date, isoDate, usLongDate, time
3. Execution time is reduced by half or more.
Sorting a 935 row * 8 columns table:
Browser Before After
-------- ------ -----
Chrome 10 90ms 42ms
Safari 5 115ms 48ms
Firefox 4 412ms 87ms
IE8 720ms 115ms
4. Based on the content language and the mdy vs dmy preference, the parser can
understand dates such as "17. März '11". wgMonthNames=[] and
wgMonthNamesShort=[]
in the content language and the mdy vs dmy preference are exported to js; A
table containing the following dates would be sorted correctly:
17. Jan. 01
23 Feb 1992
9.02.05
13 November 2001
14 Oktober '76
Was tested in ie6-8, chrome, safari 5, ff3 & ff4
