common_alg: support reversed source well log depths and data ordering

Also little fixes of processing NaN values. Now everything should work
properly, asssuming that well log data interpolation is not
implemented.
wpi: draw mesh outline if NULL or empty mask array passed to VTK algos

1) NULL or empty mask array is allowed.
2) Track such case efficiently and directly draw outline for mesh
border.
hdf5_storage: fix wrong internal sorting of base groups

Groups were sorted simply by string name, containing date & time, which
is plain wrong. Implement proper comparison of group names with full
date & time decoding from string representation, s.t. most recently
created base is always in the end of map.
wpi: fix & tune well_path_ident.py script
wpi: add min_split_threshold parameter to interface functions
wpi: remove deprecated bounds() function from mesh_part
wpi: no need in explicit mesh_part assignment operator
wpi: tune intersections builder a little bit

1. Don't create cache of well path segments, instead construct segments
online just before intersections checking. Reduce memory consumption
singificantly with zero performance impact.

2. Adapt leafs_builder to take Box* or Box& depending on boxes or their
pointers passed to CGAL::box_intersection_d.
wpi: fix facet enumeration functions syntax
wpi: allow passing strategy with _2d postfix to invoke 2D VTK algorithms
wlog_tools: fix possible crossing resulting array boundary
wlog_tools: fix possible crossing resulting array boundary
wlog_tools: check if target grid is fully outside of well log bounds
wlog_tools: check if target grid is fully outside of well log bounds
Merge branch 'wpi' into geo_main
sql_well.serialize: fix rare case when paths can be converted to UTF-8 two times
sql_well: update sqlite to version 3.8.5, fix DB open with loooong filenames
fix serialization bug for pbvd and rsvd tables
maintain versioning of pbvd and rsvd data serialization
wpi, sql_well: add only start & end well traj points for COMPDAT and FRAC

Add flag startend_only to append_wp_nodes() function, enable this flag
by default in COMPDAT and FRAC builders.