created initial loop to create array to hold results data
added getting minutes out of time in mysql query
get_gpm() achieved working label and value result array!

thanks to shantam, was able to get correctly working output
now we have a single array - $results_array wiht two sub arrays
'values' and 'labels' -

problem, the array isn't padded on the end, and will not be properly
formed if there are hours missing from the source data - currently
assumes that there will be consecutive data for every hour - no correct
changed format of the result array and added padding

the new format is [date] => [24 values]

decided to make it more generic and leave the chart labeling to an outside function

the result array is now padded to 24 values on the end, and will have
null values for hours that are missing from the source data

if an entire day is missing, that date does not currently get returned
is this bad? day 1 has data, day 2 has no data, day 3 has data - will return two days that are not consecutive. this should be fixed.
completed get_gpm function and added chart_it function

chart_it function  takes and array of data and creates a chart
currently only line chart with some fixed options.
also made changes to the calling file index.php

TODO:
* make it capable of charting other chart types
* add ability to pass in options
* add ability to pass in chart title?
* can we preserve the idea of a data table tab?
* need to move debugging to a log file, not print to screen
still need to address what to do if there are missing days in the set
-seems like i should show a full day without any data.
made date labels render correctly

dates were garbled. now they display properly and the year is at the end
added file to hold program wide constants
added logging functions
improved logging
get gpm function now returns a data table
added chart titling to chart title

can now pass in a chart title to be displayed with the chart
updated function to accept new array with data table but not display it
yet.
added display of chart data tab

displaying the 'table' sub array in the data tab. just wrapped in <pre>.

TODO:
* show each array of table data as tables with headers and a title
* ability to show / hide individual data subsets
* revealing contents of div should show in a modal that is scollable
brought gpm_test into conformity

added support html to make tabbed data and chart tabs
improved chart_it to do multiple chart types

* made it so you can pass in the chart type bar or line
* chart options are now variables set in common constants
* depending on chart type, proper chart options are loaded
added get_tanklevel to chart tank level percentage

* created new get_tanklevel function to chart tank levels
* modified chart_it to pass in chart step count and steps
* allowed for multiple charts on a page with generated canvas and div ID's
*8 worked on proper responsive display - not yet working, but improved

TODO:
* for better responsive, use javascript to force a refresh of the chart objects on resize event
added tank level alerting function using twilio

new function for sending twilio messages (from fire_geo)
new folder of twilio library (untracked)
alert.php runs as cron to check tank level and alert if over threshold
threshhold is set in constants_18.php
changed table name green_tank to readings
refactored alerts.php as reusable functions

now you can call WaterLevelLowAlert() and pass in a nodeId
and it will load the appropriate constants for that node
and run an alert check on that node's water level.

currently the function is being called earlier in the code's main loop

TODO:
add other checks as functions that take a nodeId