CR2W Serialization fixes

[nikich340]

CR2W Serialization fixes

• Makes every CVariable class SetIsSerialized() on Read(..) and SetValue(..), since these functions assume that CVar contains some data and is not "default" anymore (for SetValue it is checked if new data was really set)
• It fixes bug when some structures like tags (CBufferVLQInt32:CName) in CEntity and moduleData (SParticleEmitterModuleData) in CParticleEmitter were not marked as "edited" despite having edited children variables (what led to missing these vars in "Show only edited vars" mode in Variable Editor; and in "Dump only edited values" mode in CR2WToText/CR2WToYML)

TODO?:

• Handle special cases for classes with AddSomeVar() functions, if thery are created and edited from a code.

[rfuzzo]

Thank you. SetIsSerialized()