Fix for bug "Inline Navigator cancel after click pager"

Fix for:
https://github.com/tonytomov/jqGrid/issues/518
Grid with inlineNav.
Edit row (dont save) -> 
Click to disabled pager button "move to the first page" ->
Click to InlineNav cancel button ->
Error "Uncaught TypeError: Cannot read property 'id' of undefined" - savedRow now is empty. 
Also, reproduced in demos.
fix position of resizable icon created by gridResize
Merge pull request #523 from tpeczek/master

Fix for "TypeError: ajaxso is undefined" in Single/Advanced searching
Merge pull request #521 from OlegKi/master

fix position of resizable icon created by gridResize
Merge pull request #519 from goodTrip/master

Fix for bug "Inline Navigator cancel after click pager"
Fix avg and count parameters in getCol method. Thanks to joec2000.
Merge branch 'master' of git@github.com:tonytomov/jqGrid.git
Fix sortGrid to support frozen Columns
Add a option selectOnCollapse in subgrid which allow to select a row when it is collapsed and the option is true
Formatting fix.
fixing unneeded usage of formatter if formatDisplayField are defined

If `formatDisplayField` are defined than it could returns the string which is incorrect for `formatter`. For example if one want group date by month one want to display in grouping row soththing like `Oct-2013` or `2013-10`, but the current implementation of `groupingRender` try to call date `formatter` with the value returned by `formatDisplayField` callback. So the date are displayed with `Nan` or `Undefined`. To fix the problem I suggest to call `formatter` only in case when `formatDisplayField` callback in not defined.
Showing only top level of grouping headers in case of usage groupCollapse:true option

The current implementation of `groupCollapse:true` option display *all* groping headers and hide only the data like one can see on the picture

<img src="http://i.stack.imgur.com/saNJr.png"/>

instead of showing only groping header of the top level group:

<img src="http://i.stack.imgur.com/Pxrfb.png"/>

[The answer](http://stackoverflow.com/a/19207377/315935) discuss the problem in details.
Trying to fix namedItem function in iOS7. Let make some tests to see if it is ok
Display only the next grouping level or the data in case of expanding of groping header

The current implementation of `groupingToggle` shows **all** sub-groping headers and the data itself on clicking on the "+" icon in the groping header. Such behavior seems me not practical in case of usage deep multilevel groping.

The suggested changes the behavior so that only the headers of the next groping sub-level will be displayed in expanding of group. Only if no sub-group exist then the data will be displayed.
This is better solution for previous fix
small improvements after usage of http://www.jslint.com/
Continue to replace namedItem in the code
Introducing getGridRowById which should replace namedItem.
Replace getnamedItem with the new getGridRowById
Replace getGridRowById in treegrid and inline edit