Renamed SearchContext extension methods:

Element(s) to Container(s)
Control(s) to Element(s)
SE-15 Implement base concept of page pattern

Added lookup for IPageUrlValidator in base page classes
SE-43 Implement element selection by id
Fixed broken tests after adding Dynamic proxy
PageProxyGenerationHook throws PageInitializationException instead of Exception
Extracted BaseSelectorAttributeTest from TestIdAttribute
SE-44 Implement element selection by class

Refactored BaseSelectorAttribute in order to use convetions for test
pages
SE-44 Implement element selection by class
SE-45 Implement element selection by css selector
SE-46 Implement element selection by xpath
Fixed mistakes in comments for SelectorAttributes
SE-52 Implement element selection by name attribute
SE-53 Implement element selection by tag name
Added more tests for SelectorAttributes

Tests for private, protected and internal properties
Disabled automatic adding documentation in R# formatter
SE-47 Implement selection of a collection of elements

Added Support of Collections for Selector attributes
Fixed spelling error in class name
Updated XML documentation for SelectorAttributes