pull-request: trip manipulations

[Dirk Hohndel]

This is a somewhat more massive change. It adds most of the operations
that I think we should support on trips:
- a dive can be removed from a trip (and made a top level dive)
- a dive can be turned into a trip
- two consecutive trips can be merged
- a trip can be split in two

There are some operations that would make sense to allow on "all
selected dives" (e.g., remove from a trip and turn into a trip), but I
haven't done that part, yet.

Please review for obvious stupidities and most importantly give it a
good test... I've been banging on it for the past few days and currently
can't seem to find any corner cases where it fails, but most likely that
just means I haven't tried hard enough :-/

/D

The following changes since commit 6a210e573d947d61172da0363cbd7832e5459323:

  Add support for printing only the selected dives (2012-08-30 09:30:59 -0700)

are available in the git repository at:

  git://git.hohndel.org/subsurface.git trip3

for you to fetch changes up to c3debc10fdcb0f7e939872ea24d525f41039f5bd:

  Allow modification and edits of trips (2012-09-01 21:29:05 -0700)

----------------------------------------------------------------
Dirk Hohndel (3):
      Store time_t as long value
      Clean up macros and auxiliary functions
      Allow modification and edits of trips

 dive.h      |  42 +++++++++-----
 divelist.c  | 503 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++-----------------
 info.c      |  62 +++++++++++++++++++-
 parse-xml.c |   8 +--
 save-xml.c  |   4 +-
 5 files changed, 547 insertions(+), 72 deletions(-)