Add reserve to TrajectoryBase

[snozawa]

Summary

• Add Reserve API to TrajectoryBase and implement it for GenericTrajectory.

  Description

• Insert might be called from the time-critical code path. To mitigate the risk of dynamic memory allocation inside of Insert, implement Reserve API.
• Reserve API has options flag, so that the user can decide whether to save _vtrajdata only or to save _vtrajdata and other data altogether. Other data like _vaccumtime might not be used as long as the user does not use Sample-related APIs. In such case, the user might want to skip unnecessary memory pre-allocation.

[rdiankov]

@snozawa I understand the need. But in the interest of keeping the API clean and not having to worry about calling Reserve after Init is called, how about adding a second parameter to TrajectoryBase::Init instead, which will only allow the user to reserve the points on initialization of the trajectory?

[snozawa]

@snozawa I understand the need. But in the interest of keeping the API clean and not having to worry about calling Reserve after Init is called, how about adding a second parameter to TrajectoryBase::Init instead, which will only allow the user to reserve the points on initialization of the trajectory?

thanks for your comment! That makes sense! I updated Init function to support reserving of memory, and by default, reserving is disabled.

[rdiankov]

Thanks!