Change where to check for weight
dict: do not store headword vector.
create (and use) serialized graphs
Add --nopos option to compile_kb (necessary when serializing dictionaries without pos)
use unordered set instead a map in directory
Change data structure for wdict_pos_range, so it uses less memory.
common: optimize vectors when reading from stream.
wdict: compute overheads.
Change WDict structure so it has less memory overhead.
Introduce new vector class for holding dict entries.

The new wdict_vector has less overhead.
wdict: make it compile on a g++ ver 4.7.2
Remove output_semcor option.
csentence: Remove unused functions.
csentence: re-introduce some CWord functions (begin, end), which are used in disambgraph
csentence: big change in aw parsing function. Now "noppv" elements are dealed properly.
Add a "noppv" test in dotest input.
test: Add a script for automatically checking results.
Introduce a cw_ctxword_nopv element in contexts (value 4). It is like cw_tgtword_nopv, but it is not disambiguated. It is useful for grouping concepts.
changes in README
ukb_wsd: factorize out the code calling the proper disamb. method.