fix step sequence iterator

[dqyi11]

In current aikido, unexpected exception is thrown in some cases.
StepSequence seq(0.2, false); for (double v : seq) { DART_UNUSED(v); count++; }
An exception will be throw

unknown file: Failure
C++ exception with description "Indexed maximum intenger." thrown in the test body.
Expected sequence shall be (0.0, 0.2, 0.4, 0.6, 0.8); but getMaxSteps() returns 6.
Thus an exception is triggered in operator [].

In this PR,
StepSequence seq(0.2, true) returns (0.0, 0.2, 0.4, 0.6, 0.8, 1.0) and getMaxSteps() returns 6.
StepSequence seq(0.2, false) returns (0.0, 0.2, 0.4, 0.6, 0.8) and getMaxSteps() returns 5.
Unit tests are updated accordingly.

• Document new methods and classes (N/A)

• Format code with make format

• Set version target by selecting a milestone on the right side

• Summarize this change in CHANGELOG.md (N/A)

• Add unit test(s) for this change

[codecov]

Codecov Report

Merging #305 into master will decrease coverage by <.01%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master     #305      +/-   ##
==========================================
- Coverage   81.13%   81.12%   -0.01%     
==========================================
  Files         204      204              
  Lines        5893     5891       -2     
==========================================
- Hits         4781     4779       -2     
  Misses       1112     1112

Impacted Files	Coverage Δ
src/common/StepSequence.cpp	100% <100%> (ø)	⬆️

[brianhou]

Thanks for fixing the tests! I left a minor suggestion about the logic in this method.

[brianhou]

I found the current logic somewhat difficult to follow. Can we do something like:

int numSteps = (mEndPoint - mStartPoint) / mStepSize;
if (fabs(mStartPoint + mStepSize * numSteps - mEndPoint) > 1e-7)
  numSteps++; // include start
return numSteps + mIncludeEndpoints;