New field descriptor format.

Now field information is stored as a variable-length uint32_t array.
This reduces the minimum size in most cases:

old new
basic field: 10 bytes 4 bytes
repeated field: 10 bytes 8 bytes
field with 12bit tag/size: 16 bytes 8 bytes
field with 16bit tag/size: 16 bytes 16 bytes
field with 32bit tag/size: 28 bytes 16 bytes

Further, now the descriptor size can be increased per-field and per-message,
instead of previous global PB_FIELD_16BIT and PB_FIELD_32BIT.

PB_FIELD_32BIT still affects the pb_size_t type, which is 16-bit by default.

Big refactoring to better separate field descriptor encoding from logic.

This will enable further development of the field descriptor encoding.

Combine pb_encode_varint32() into pb_encode_varint()

Unit test updates for the string length

unit test fix for checking string encoding length

Add pb_encode_varint32 and pb_encode_svarint32

- Optimized 32 bit versions of pb_encode_varint and pb_encode_svarint

Add a few missing unit tests

Change the _count fields to use pb_size_t datatype.

Update issue 82
Status: FixedInGit

Separate field iterator logic from pb_decode to pb_common.

Add a convenience function pb_get_encoded_size()

There is minimal size penalty from this, and it is probably much more
intuitive to use than PB_OSTREAM_SIZING itself.

This has been suggested before also, but I ended up refusing it back
them. Reconsidering it now, I see that an intuitive API is much better
than any amount of documentation explaining a non-intuitive API.

Update issue 16
Status: FixedInGit

Remove the NANOPB_INTERNALS functions from public API.

These have been deprecated since nanopb-0.1.6 (some since 0.1.3).
Equivalent functions with better interface are available in the API.

Update issue 91
Status: FixedInGit

Detect invalid sizes when encoding bytes fields.

Check array max size when encoding.

Update issue 90
Status: FixedInGit

Add #defines for the maximum encoded message size.

Update issue 89
Status: FixedInGit

Start moving the tests into subfolders. Transition to SCons for build system for the tests.

Only a few tests updated so far. Have to include all the rest before merging to mainline.

Update issue 63
Status: Started