Add support for complex objects, namely PSCredentials in Private functions

[iricigor]

For example, PSCredentials can be parsed as username + password fields in index.html and in run.ps1 it will build PSCredentials from these two input values

[iricigor]

What examples are good?

[iricigor]

In the total, list of tasks is:

• update Convert-ParametersToHTML - to generate two merged fields: username and password
• update Convert-ParametersToRunner - to create a PSCredential object based on sent username and password
• add a test: created HTML file should have Credential-UserName and Credential-Password objects
• add an example: create New-PSDrive to some read-only share on my VM and then run Get-ChildItems or Get-Content there. The example requires -PostCode switch which will be implemented in Add -PostScript parameter #27

[iricigor]

Code ready for testing online, example still missing

Gonna merge in order to pickup other changes

[iricigor]

Added some basic example (Invoke-Command), but still no meaningful example. New issue #39 opened for that.