Tasks connected with tooltip.

Here I have included next tasks:
[MAGN-4765](http://adsk-oss.myjetbrains.com/youtrack/issue/MAGN-4765) DUI: If Desc and pic missing from tooltip - remove the top part
[MAGN-4615](http://adsk-oss.myjetbrains.com/youtrack/issue/MAGN-4615) DUI: Some tooltips' margins are off
[MAGN-4672](http://adsk-oss.myjetbrains.com/youtrack/issue/MAGN-4672) DUI: Tooltip content for inputs and outputs
For query/actions: Have the name that is shown on the inputs.
![image](https://cloud.githubusercontent.com/assets/8158404/4418054/8df4818e-455b-11e4-86a7-746421c5e087.png)
For create: Have the name that is shown on the output.
![image](https://cloud.githubusercontent.com/assets/8158404/4418161/66321804-455c-11e4-8982-e6971737450a.png)

[MAGN-4379](http://adsk-oss.myjetbrains.com/youtrack/issue/MAGN-4379) DUI: Change the tooltip fade out time to 0.5 seconds

# Reviewers
@Benglin,@vmoyseenko, please take a look.
The base ```NodeSearchElement``` is not supposed to know about a derived class, this is a violation of inheritance in OOP. Use ```protected virtual IEnumerable<Tuple<string, string>> GenerateInputParameters()``` virtual method.