factor out computing actual take amounts
use variable names in interpolation
support using compute_actual_takes() inside a transaction
cache a user's takes in a new column of the participants table
update receiving amounts of members when changing team takes
don't forget takes when recomputing receiving amounts
add test to prevent regressions
drop the `process_take` function when we're done
Failing test for when team receiving changes

Ref: https://botbot.me/freenode/gittip/2014-06-17/?msg=16423375&page=2
Use member as recorder in team take tests

Closer to reality.
Simplify team take tests

The team name knob was never actually used.
Clean up whitespace a bit in take tests

We're at 100 char lines now.
Make take tests clearer wrt team member takes

Before we were hardwiring 'alice' as the only team member that we would
set a previous take for. I want to write tests for the interaction
between takes for multiple member, so I need to be able to set
take_last_week for multiple members.
Passing test for entanglement of member takes

When a member changes their take it affects the computed `takes` for all
other team members.
Test that get_members uses nominal take
Another test for take receiving interaction
Test for including takes when updating receiving
Here's a couple tests for update_receiving_amounts

Including one for including takes in receiving.
failing test for team's `takes` being zero
move the `takes` updating logic into its own method