Replaced the confusing pb_enc_* functions with new pb_encode_* functions that
have a cleaner interface. Updated documentation.
Got rid of the endian_copy stuff in pb_encode.c, instead using C casts to do it automatically.
This makes the code safer and also reduces binary size by about 5%.
Fixes Issue 6.
Most importantly, callback fields in submessages were being overwritten with garbage, causing segfaults.
Additionally, converted PB_LTYPE_FIXED to PB_LTYPE_FIXED32 and PB_LTYPE_FIXED64. This makes the interface
a bit easier to use, and in addition runs faster.
git-svn-id: https://svn.kapsi.fi/jpa/nanopb@975 e3a754e5-d11d-0410-8d38-ebb782a927b9
