Update Upload.php

fix for

Fatal error: Call to undefined method ErrorException::addMoreInfo() in /atk4/lib/Form/Field/Upload.php on line 154
Merge pull request #420 from rvadym/master

Update Upload.php
Model->set(), fix for "dirty" comparison

I hope this way it'll work better, because old
(string)$value!==(string)$this->data[$name] don't work well for boolean value fields.
For example, (string)"1" !== (string)1 or (string)true will return true and as result set field as dirty.
We should use loose comparison != here instead, but at the same time take care of NULL values, because these need special treatment (as always) :P
Form_Field_Readonly: now works nicely with ValueList based fields

This is cool ! :)
Now readonly form fields at last nicely can replace ValueList based form fields like DropDown, Radio, CheckboxList. Readonly field will not show ID anymore, but get and show related model title field value (with just one simple SQL request).
Form_Field_ValueList: nothing much
Merge pull request #422 from DarkSide666/patch-3

Model->set(), fix for "dirty" comparison
Merge pull request #424 from DarkSide666/patch-5

Form_Field_ValueList: nothing much
grid template: take care of floats

where there is no records in grid and no buttons, but have right floated quicksearch, then notfound message should clear floats otherwise it is shown above quicksearch widget.
Model: fix "dirty" even more

Still needed to add special treatment of `false` value
Merge pull request #426 from DarkSide666/patch-3

grid template: take care of floats
Merge pull request #427 from DarkSide666/patch-5

Model: fix "dirty" even more
Model: "dirty" fix nr.3

Yes I know, I know ...
There still was problem with situations when:
1) $this->data itself is null !? Can't explain why this happens - probably some ATK4 magic :)
2) $this->data[$name] is initialized, but it's value is NULL. As result isset($this->data[$name]) still return false if value of array element is NULL.

well - this change fix both cases.
Merge pull request #428 from DarkSide666/patch-3

Model: "dirty" fix nr.3
Merge pull request #423 from DarkSide666/patch-4

Form_Field_Readonly: now works nicely with ValueList based fields
prevent hidden errors occur when forms submitted without ajax
Form_Field_Readonly: more value_list fixes

Slightly modified this part. Now it works with model based fields (like DropDown with associated model) *and* also fields without associated model like the ones defined as `$model->field->listData(array(0=>'Person',1=>'Company'));`
Merge pull request #429 from DarkSide666/patch-3

Form_Field_Readonly: more value_list fixes
changes what make Form_Field_Upload class more friendly for inheritance
Merge branch 'master' of github.com:rvadym/atk4
Merge pull request #430 from rvadym/master

Сhanges what make Form_Field_Upload class more friendly for inheritance