preventing multiple simultaneous save requests to create multiple docs on storage
tentative fix of race condition on entities when created from app42 callback
fix build error by commenting old pvp test code.
changes in download design to use only one version number where the 3 first are the app number and the last one is the data version, relative to the app version.
fixing copy paste error in update code.
fixing joining / splitting version to allow optional "v" at the beginning.
fixes for downloading assets and forcing reload of already loaded assets.
implementing to_string for android. ndk doesnt have it yet.
making splitVersion() more robust. now assuming empty version string is 0.0...
adding logs and fixing build on android.