DUI: new templates

This PR should be merged after [that](https://github.com/Benglin/Dynamo/pull/170) one.

# Preface
With new updates it appears, that members, classes and nested classes can be at the same level. EB has elaborated new piece of design for us.
![image](https://cloud.githubusercontent.com/assets/8158404/4897515/18aee5b6-6407-11e4-8bc8-9f026602b101.png)
![image](https://cloud.githubusercontent.com/assets/8158404/4897520/207a843a-6407-11e4-94c5-a3dba9ec5182.png)

As you can see, now we need to introduce new template for methods button and categories(as operators) don't need Actions, as it was before.
![image](https://cloud.githubusercontent.com/assets/8158404/4897547/77189bc4-6407-11e4-86d9-e81846a19b65.png)

# Solution
`CategoryClassDetailsTemplate` was replaced with `MemberTemplate`. In converters was added `NodeSearchElement`.

# After
![image](https://cloud.githubusercontent.com/assets/8158404/4897736/e73b4838-6408-11e4-928a-27f095b0e700.png)
![image](https://cloud.githubusercontent.com/assets/8158404/4897742/ef4cf134-6408-11e4-810c-5a0866e0248a.png)

# Reviewers
@Benglin ,@vmoyseenko, please take a look.

Link to YouTrack:
[MAGN-5262](http://adsk-oss.myjetbrains.com/youtrack/issue/MAGN-5262) DUI: Make the same margin for all members
It seems like ```SmallIcon``` is already having margin of ```16,0,16,0```, is this trigger needed?