Add section about JVM memory settings under MATLAB (rebased onto dev_4_4)



This is the same as gh-830 but rebased onto dev_4_4.

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Default JVM settings in MATLAB are fairly low (max heap size 196M for most recent 64-bit version) and easily result in OOM when opening large files. This PR adds a section to the MATLAB developer documentation page documenting how to increase the maximum heap space and proposing a default value of 512M.