lidar2camera/manual_calib: Fix Eigen vector allocations

[juliangaal]

Fixes Eigen allocations in manual calibration. The code was faulty for two reasons:

• Vector not properly initialized. Memory only reserved (.reserve(12)), yet init method accessed uninitialized memory -> Core dumped
• Using an alligned allocator to not trigger Eigen runtime assertions

[juliangaal]

Can you share the Dockerfile used to build opencalib_v1? I am using one I wrote myself with updated pangolin, because opencalib_v1 errored sometimes with pangolin errors. Yet, I have not tested my image with all tools