Multiple project fixes

* Change 'EnableEnhancedInstructionSet' from 'StreamingSIMDExtensions' to 'NotSet' in common.props
* Enable Whole Program Optimization (LTCG) for Release configurations all projects
* Add "Release Unicode" & "Debug Unicode" as 'Or' conditions to common.props
* Change "Release_Unicode"/"Debug_Unicode" to "Release Unicode"/"Debug Unicode"
* Rename forgotten "Release Unicode|x64" configuration to "Release|x64" in libssf
* Set /Ob1 and /Os for libssf
Moved log4cplus to thirdparty
Moved gtest to thirdparty, renaming the dir to gtest

This should make updating it easier
Renamed Boost dir to make updates easier
Google Test library updated from v1.6.0 to v1.7.0
Update VirtualDub library to v1.10.1-test12 (MPC-HC)
Backport static UnRAR from MPC-HC
Fixes for unrar

* Set /Ob1 and /Os for release configuration
* Move USE_UNRAR_STATIC define to vsfilter_config.h