Add ec_dec_tell() to report the same information as ec_enc_tell() decode side....

Add ec_dec_tell() to report the same information as ec_enc_tell() decode side. Remove ec_enc_tell() and replace it with ec_enc_tellf(): just request 0 fractional bits if you want an integer value.

git-svn-id: http://svn.xiph.org/trunk/ghost@14394 0101bb08-14d6-0310-b084-bc0e0c8e3800