fixed a performance bug in matching

 Using links or other "non-simple" variables in the score expression made things a lot slower than necessary because the "system temporary variables" kept accumulating and context_subset was increasingly costly.
(cherry picked from commit b0aaa1e)
added notes & links to issue 128
(cherry picked from commit 04dff9b)
added a Qt implementation of our progressbar and added a "precise" option to time2str
added one more h5 tool: idshrinker

It renumbers ids starting from 0, and keeps all the links synchronized. There is also a small bit to change all 0 to -1 in link fields.
* added command line argument (-p/--progress) to enable reporting of global/simulation progress, it does not play well with (interactive) charts though.
* added a title argument to loop_wh_progress to set the title of the window and use it for all instances of loop_wh_progress
* show top times now also show the % of total
* added optional "user value" label in progressbar dialog (eg show current period for the simulation progress)
Merge branch 'liam2-127'
* made expand_wild return a set (to reflect the fact that the resulting list is not ordered)
* fixed exception message in field_str_to_type
allow loading globals from csv files directly (closes #30)

This means the dataset do not need to be imported again if only the globals changed.
style
flushes output_index/id_to_rownum to disk for periods < period - 1 (closes #130).
draft of changelog for 0.8.2
kill bad newline
added piwik tracking to documentation

moved included files to _templates because all files in _static are exposed to the world and there is not point of doing that for those files
better version number
silence lint warning
add cytoolz/DistArray
upgrade carray to bcolz
added some info about how to install vitables
link to PySide port of ViTables
removed all Qt progressbar stuff as it is too fragile currently and it would take too much time to "do the right thing"
remove -p command line switch
more GUI stuff removal
add new "logging" keys in yaml_layout (not implemented yet)