[Tracker] indexer-split branch missing lots of important stuff

[Jamie McCracken <jamie mccrack googlemail com>]

Compared to trunk, an awful lot of essential functionality has been
removed in the indexer-split.

Apologies if they are elsewhere and I have missed them in the code but
if not these need to be restored form trunk before i give approval for
merge

These are:

1) temp blacklisting of files that change frequently - see revision 1149
and 1169 in trunk

2) low disk space limit (cant see this used anywhere)

3) stop words in tracker-parser.c - why did you remove this?

4) index merging - where did this go? Without this indexing wont scale
up (its slow updating a large index) + you will suffer from
fragmentation and wasted disk space due to hashtable resize relocations
(these are never recovered) - merging solves both these issues

5) evolution on startup should scan any changed summary files for new
junk or deleted items and remove them from index - see trunk for this

there is probably more but all the above are very important

jamie