Add a bindep.txt file so CI does not use the defaults and we are
explicit about the python-dev dependency.
Add a note to the manual installation instructions explaining the need
for the Python source headers.
Change-Id: Ida4b897da4bdc3284a131166fdfa17bc9a4b1abd
Signed-off-by: Doug Hellmann <doug@doughellmann.com>
bd054fd5dc