Rename timer `Setup` function to `Schedule`

This patch was motivated by my desire to fix a typo in the function
name. The noun "setup" is 1 word. The verb "set up" is 2 words. All
other member functions are verbs, so this one should be a verb too.
That means that the function should be called `SetUp`. During the
discussion that resulted from the rename, James Kuszmaul pointed out
that "setting up" a timer can be confusing. It implies that you can
only "set up" a timer once. But the intent is to let users set up
timers as many times as they like. So we decided on renaming the
function to `Schedule`. That conveys the purpose and intent better.

I took this opportunity to fix some other typos involving the verb
"set up".

Signed-off-by: Philipp Schrader <philipp.schrader@gmail.com>
Change-Id: I2f557d1f946960af82711f248820d5e2d385a5d3
diff --git a/frc971/vision/target_mapper.cc b/frc971/vision/target_mapper.cc
index e7a6955..7778da1 100644
--- a/frc971/vision/target_mapper.cc
+++ b/frc971/vision/target_mapper.cc
@@ -367,7 +367,7 @@
 
 std::unique_ptr<ceres::CostFunction>
 TargetMapper::BuildMapFittingOptimizationProblem(ceres::Problem *problem) {
-  // Setup robot visualization
+  // Set up robot visualization.
   vis_robot_.ClearImage();
   constexpr int kImageWidth = 1280;
   constexpr double kFocalLength = 500.0;