Log Message:
Update serd to 0.30.0.

Incidentally, this fixes compilation with Python 3.7.

Serd 0.30.0

  * Upgrade to waf 2.0.9 and autowaf a328983
  * Fix length of base64 encoded nodes
  * Clarify errors returned by serd_env_expand()
  * Fix reported error when reading statements with only a blank node
  * Fix parsing local names that end with escaped dots
  * Improve relative URI serialisation
  * Add serdi option to write ASCII output
  * Make serdi guess input syntax from extension if unspecified
  * Make serdi syntax options case-insensitive
  * Add basic error tolerant parsing for line-based formats
  * Support strict parsing of prefixed names
  * Report errors for all failing test cases
  * Use more efficient stack allocation and growth policies
  * Add NTriples test suite
  * Fix building with MSVC
  * Clean up testing code
  * Add serd_free for freeing memory allocated by serd

Serd 0.28.0

  * Add support for reading from a user provided callback
  * Add serd_node_from_substring()
  * Fix strict parsing of abolute URI schemes
  * Fix parsing of hex escapes in file URIs (thanks Johannes Mueller)
  * Gracefully handle applications that write corrupt UTF-8
  * Fix hangs when reading corrupt UTF-8

Serd 0.26.0

  * Add support for TriG and NQuads
  * Add support for braindead SPARQL PREFIX and BASE directives

Serd 0.24.0

  * Add serd_node_new_relative_uri()
  * Fix construction and comparison of URIs with UTF-8 characters
  * Report I/O errors with message and return appropriate status code
  * Report missing statement separator errors
  * Fix potential out of bounds read
  * Fix unaligned memory access, undefined behaviour which breaks on ARM
  * Fix documentation generation
  * Update serdi man page

Serd 0.22.0

  * Remove dependence on fmax() to avoid portability issues
  * Fix serd_reader_read_file() for URIs with escaped characters (spaces)
  * Add serd_reader_set_strict() and -l (lax) option to serdi to tolerate
    parsing URIs with escaped characters
  * Fix reading statements ending with a blank then dot with no space
  * Fix clash resolution when a blank node ID prefix is set
  * Fix serializing fractional decimals that would round up
  * Add support for Turtle named inline nodes extension
  * Report errors for invalid IRI characters and missing terminators
  * Show serdi errors in standard format
  * Fix warnings when building with ISO C++ compilers
  * Upgrade to waf 1.8.14