using context for parsing
Merge pull request #63 from jdeng/fix1

Using context for parsing.
Added define for minimal compatibility with legacy smart pointers.
Merge branch 'master' of https://github.com/kisli/vmime
Merged source and header files in directory structure. Got rid of SConstruct build.
Update HACKING
Fixed path to header files. Removed useless echoes.
Added support for APPENDUID/COPYUID (UIDPLUS extension for IMAP).
Merge branch 'master' of https://github.com/kisli/vmime
Added support for RFC-3348 (Child Mailbox extension for IMAP). Renamed FLAG_CHILDREN to FLAG_HAS_CHILDREN.
Do not expose internal constants.
Added support for SPECIAL-USE extension (IMAP).
Loop on SSL_write/gnutls_record_send in blocking send.

OpenSSL reports SSL3_WRITE_PENDING on slow network connections, this
patch fixes it (and is the correct way to do).
Allow "200" response code to RSET command, as per RFC-876.
Do not wait for server response to QUIT command.
Do not disconnect after recoverable error.
Use block size of underlying stream.
Report sending progress when chunking is supported.
Check for NULL progress listener.
Use non-blocking send in GNU TLS push callback.