build.bat: Add /Analyze switch.
Partially revert 2115f0f
Merge pull request #83 from alexmarsev/revert

Partially revert 2115f0f
CIfo: fix a couple of warnings

It's safe to use explicit casts, all necessary checks are in the 'if' already
CIfo: more safe file opening
CMpcAudioRenderer: fix a warning

The 'if' ensures that cast is safe
Also remove the cast in aforementioned 'if'
CBaseMuxerOutputPin: fix a warning

The casted value is basically si->dwOffset, which is DWORD
CWebClientSocket: fix a warning