Use paths relative to src in #include directives

This commit changes all #include directives to use paths relative to the
src directory, eg. "master/filesystem.h" instead of "filesystem.h". This
is to make our code less messy and more compliant with Google code style.

Two headers are included in the old way: config.h (which is generated
at build time and located in the directory, where sources are compiled)
nd init.h (which has many different locations and the right one is
chosen using -I compiler flag).
Sort include files according to Google guidelines

This commits sorts include directive in 11 files, where these directives are
mixed with some other preprocessor direcives (eg. #ifdef). This makes
automatic sorting more difficult, so I made this manually.
Sort include files according to Google guidelines

This commit sorts include directives in all the source files except these
files, which were fixed manually in the previous one. All the changes in
this commit were made by a script, except:
* the declarations and definitions of queue_put and queue_get were
  different and the code failed to compile after including pcqueue.h
  in pcqueue.cc, so I've fixed this bug.
* <stdint.h> was missing in cscomm.h and dirattrcache.h. The code
  failed to compile after moving this includes to the front of their .cc
  files, so I had to fix these two headers.