Fixed conditional
WP doens't support AllowPartiallyTrustedCallers
CF doesn't support AllowPartiallyTrustedCallers
Drop support for NLogC
Remove NLogC from installer
Remove components from installer
Add SecuritySafeCriticalAttribute to all FileAppenders
Add conditional compiler directive
Add more SecuritySafeCritical
Add more SecuritySafeCriticalAttribute
Set SecurityRule attribute

Otherwise Level2 is used in .NET 4 or above, which doens't work correctly
for other versions
Do not use SecurityRules under Mono
Do not use SecurityRules in .NET 2.0
Revert "Drop support for NLogC"

This reverts commit a55a3ebc7e4512f81a5e96d568bd936830aef920.