Update float parsing using InvariantCulture to not depend on OS language to parse float value.
Usefull for French, German, ... users where comma is default notations for the decimal point parsing.
Previously, `vfs->filedata` memory was allocated via `mju_malloc` in C and released using `Marshal.FreeHGlobal` in C#. In 5cc73c30bf, `mju_malloc` started returning 64-byte aligned pointers, which should not be freed by a deallocator that isn't aware of this alignment.
Fixes#479.
PiperOrigin-RevId: 474596441
Change-Id: I8a8383c7eaa2c1ec516d81f92a2f90e7aedfe2ee
This also fixes a sensor data reading bug: previously, _sensorIndex was multiplied by 3 by MjEngineTool.
PiperOrigin-RevId: 451699887
Change-Id: I864bcbf8159857764854b25311a26ec5672125d9
Copybara-Service