Added support for objects which override the ToString method in SessionModelConverter

SessionModelConverter only had support for types marked as Serializable.
With this change, it also checks if the type has overridden the ToString
method in which case it calls it. If the type is neither marked as
serializable nor has the ToString method, then the "Non serializable
type" error message is shown in the Session tab.
Added unit tests for SessionModelConverter
Fixed and refactored SessionModelConverter unit tests

Some incorrect Assert's were fixed.
Fixed whitespaces in last commit
Merge branch 'master' of https://github.com/vape/Glimpse

Conflicts:
	source/Glimpse.Test.AspNet/SerializationConverter/SessionModelConverterShould.cs
small refactorinigs
add missing line
Merge pull request #327 from vape/master

Added support for objects which override the ToString method in SessionModelConverter
Fix reference to Glimpse screenshot in README
Fix #313 - Added documentation link
Update #325 - Glimpse metadata now returns a configuration hash code that can be used for proper cache busting. Client needs to be updated to leverage this code for update notifications.
Fix #329 - Added a check which doesn't override if not set
Fix #247 - Removed the client cache busting

Used server no-cache controls
Update #325 - First cut at switching over to new hash
Fix #325 - Finial fixes for version check
Update #325 - Update in-client version update notification
Minor code refactoring
Remove unneeded code
Fix up a typeo
Switch over some manual selector code over to use existing functions