core: use default hash/comparison callback for keys of type integer/pointer/time in hashtable
core: use size of 32 for hashtables (instead of 4, 8 or 16)

A size of 32 will use a little more memory but will reduce collisions in key
hashs, and then length of linked lists inside hash structure (faster search in
hashtable).
Merge branch 'master' of git://git.sv.gnu.org/weechat
core: fix hidden lines for messages without date when option weechat.history.max_buffer_lines_minutes is set (bug #38197)
core: add "/debug tags" in /help filter
irc: fix typo in comment
doc: fix typo in user's guide
core: fix detection of python on Ubuntu Raring
aspell: optimization on spellers to improve speed (save state by buffer), add info "aspell_dict", add completion "aspell_dicts"

Two hashtables have been added to store the spellers currently used (in all
buffers) and info for each buffer: array with pointers to spellers and state of
aspell for this buffer.
Therefore the spellers are not destroyed and created again on each buffer switch,
or each time screen is refreshed when window is split.
relay: add comments with example of messages in weechat protocol
relay: add return of a NULL pointer in command "test"
doc: add description of command "test" in relay protocol
core: add info about doc and function to read in /help weechat.completion.default_template
core: add file .gitattributes to exclude some files from tarballs

Files excluded: .git* (.gitignore, .gitattributes), weechat.spec
Directory excluded: debian/
core: remove weechat.spec from EXTRA_DIST target
relay: fix typo in comment
relay: fix commands sync/desync in weechat protocol (bug #38215)

Fix:
- use proper arguments in commands sync/desync (use argv[0] instead of argv[1])
- when searching if a buffer is synchronized, its name has higher priority on "*"
  (so first check if buffer is synchronized, and if not found, search if "*" is
  synchronized)
- when receiving a "nicklist_*" signal, check if the buffer is synchronized with
  flag "RELAY_WEECHAT_PROTOCOL_SYNC_NICKLIST"
core: update italian translations
core: fix refresh of line after changes with hdata_update (update flag "displayed" according to filters)
doc: update german translations and scripting guide