[PATCHv4 0/2] Implement the GIT_TRACE_CURL environment variable

This is the fourth version but in reality is the complete rewriting of the patches discussed here (here called V1)

$gmane/290520 $gmane/290521

*Changes from V3 ($gmane/292040)

- add missing static to curl_dump
- reorder the patch order
- tried to fix all (but i am not sure) the problems reported by Julio ($gmane/292055)
- * squash the documentation with the http.c commit.
  * in the trace prefix each line to indicate it is about sending a header, and drop the 
    initial hex count
  * auto-censor Authorization headers by default 

    as suggested by Jeff King ($gmane/292074)

*Changes from V2 ($gmane/291868)

- fix garbage comment in http.c (i am very sorry for that)
- add final '.' to the commit message for imap-send.c and to other commit messages
- typofix double ; in http.c
- merge the nice cleanup and code refactoring of Ramsay Jones (Thank you very much !!)
- squash the previous commit 2/4

*Changes from V1

- introduced GIT_TRACE_CURL variable with its documentation
- changed the name of the temporary variable "i" in "w" in the helper routine
- used the c escape sequences instead of the hex equivalent
- dropped the previous GIT_DEBUG_CURL env var
- curl_dump and curl_trace factored out to a shared implementation
in http.c
Elia Pinto (2):
  http.c: implement the GIT_TRACE_CURL environment variable
  imap-send.c: introduce the GIT_TRACE_CURL enviroment variable

 Documentation/git.txt |   8 ++++
 http.c                | 109 +++++++++++++++++++++++++++++++++++++++++++++++++-
 http.h                |   4 ++
 imap-send.c           |   6 +++
 4 files changed, 126 insertions(+), 1 deletion(-)