As the number of log files on the SD card grows, the JSON file list no longer fits easily in memory causing numerous bugs

[parkercoates]

In our experience, this happens at around 80 log files, but like all things related to memory usage/fragmentation the behaviour non-deterministic.

Things that break when the file list fails to allocate or consumes all available memory:

1. All data on the status.htm webpage (since the status message includes the full file list)
2. The status table on index.htm webpage (for the same reason as above)
3. Downloading the file list on the status webpage
4. Downloading all logs zipped together (although this one probably isn't going to work with a large number of log files anyway)
5. Auto upload of files. Making an SSL connection requires a few large chunks of contiguous memory and is quite susceptible to memory exhaustion/fragmentation.