Add support for dynamic buffer sequences.
This commit adds:
- New dynamic_string_buffer and dynamic_vector_buffer adapter classes that meet
the DynamicBufferSequence type requirements.
- New dynamic_buffer() factory functions for creating a dynamic buffer adapter
for a vector or string.
- New overloads for the read(), async_read(), write() and async_write(),
read_until() and async_read_until() free functions.
N.B. the read_at, async_read_at, write_at and async_write_at functions have not
yet been updated to support dynamic buffer sequences.
11 files changed
