[html] Don't ever start a series with null builds
[html] Cut the size of _buildSeries() in half
[html] Ensure graph range is exactly what is passed to setZoomRange
[html] Strip unused range finding code from buildSeries
[html] Calculate and use useful data range for graphs
[html] Properly use timerange for gDataRange
[html] Check if we need full-resolution data on initial graph render
[html] Remove now-useless logMsg

Used to differentiate between condensing modes, now there's only one.
[html] Pad gDataRange if there is only one timestamp
[html] Don't get confused when grouping distance is zero

Previously zooming in too far with too low of a gMaxPoints value would
cause grouping distance to be zero, resulting in groupin() always
returning NaN
[html] Fix remaining groupdist Infinite/NaN errors
[html] Fix zoom out button erroneously appearing in some situations

setZoomRange(undefined) triggered a "zoom out" that hid the button, but
setZoomRange(self.dataRange) did not
[html] Improve help text for try builds
[util/import_flatfile.py] Support setting mode->replace to nuke old tests when importing
[html] Remove nocondense special casing

It is equivalent to maxpoints=0 now, and the plot will do the right
thing
[tester_scripts] Properly export custom-xxx series
[util] Make archive_db.sh a little more verbose
[util] Remove xz weirdness in archive_db.sh
[create_graph_json] Update for new DB format
[util] Don't prioritize builds in queue_tinderbox_builds.py