Raise FILE_SIZE_HIGHLIGHT in the sample configuration to a useful level
The current default limit is far too low for a lot of text files.
For many local instances, it is highly desired to have syntax highlighting
for most, if not all content stored. The limit being set here has been
tested with constrained local instances to render appreciably well without
making things slow.
Signed-off-by: Neal Gompa <ngompa13@gmail.com></ngompa13@gmail.com>