…ore processing

Currently all the DOM manipulations are handled in a loop after Mustache
template is parsed. This causes severe performance issues especially within
loops iteration over thousands of (attempt/application) records and causing
all kinds of unnecessary browser work: reflow, repaint, etc.

This could be easily fixed by preparing a DOM node beforehand and doing all
manipulations within the loops on detached node, reattaching it to the document
only after the work is done.

The most costly operation in this case was setting innerHTML for `duration`
column within a loop, which is extremely unperformant:

https://jsperf.com/jquery-append-vs-html-list-performance/24

While duration parsing could be done before mustache-template processing without
any additional DOM alteratoins.

Check whether to display pagination or not on large data sets (10-20k rows)
was taking up to 50ms because it was iterating over all rows. This could be
easily done by testing length of array before passing it to mustache.

Logic related to `hasMultipleAttempts` flag:

 - Hiding attmptId column (if `hasMultipleAttempts = false`)
 - Seting white background color for first 2 columns (if `hasMultipleAttempts = true`)

was updating DOM after mustache template processing, which was causing 2 unnecessary
iterations over full data set (first through jquery selector, than through for-loop).

Refactoring it inside mustache template helps saving 80-90ms on large data sets (10k+ rows)

Refactoring incomplete requests filter behavior due to inefficency in DOM
manipulations. We were traversing DOM multiple times just to hide columns
that we could have avoided rendering in mustache (end date, duration).
Factoring this logic in mustache template (`showCompletedColumn`) saves
70-80ms on 10k+ rows.

Detaching history table wrapper from document before parsing it with DataTables plugin
and reattaching back right after plugin has processed nested DOM. This allows to avoid
huge amount of browser repaints and reflows, reducing initial page load time in Chrome
from 15s to 4s for 20k+ rows

…ependency"

Upgrade of HtmlUnit seems to bring new dependencies and since it is not required
for the purposes of PR (`HistoryServerSuite` tests pass anyway on our Jenkins),
we revert HtmlUnit version change

This reverts commit 96598ab.