Removed the old native collator jar file

Removed libs/td_collator_so.jar as all native libraries are now loaded from couchbase-lite-andriod/jniLibs.
This is also a part of fixing UnsatisfiedLinkError reported from the following issues :

https://github.com/couchbase/couchbase-lite-android-liteserv/issues/12
https://github.com/couchbase/couchbase-lite-android-liteserv/issues/13