Make exportNotebook work with new reMarkable versions plus other features

[jackjackk]

Tested with rM v1.7.2.3 and v1.8.1.1. Below the list of major changes

• update rm2svg to a 0.0.2 version found in another fork which seems to work with v3 lines format (https://github.com/lschwetlick/maxio/tree/master/tools)
• use find_document and rmtgrep to find matching documents, the same functions used in repull.sh from https://github.com/reHackable/scripts (eventually I think all these should be consolidated, as many helper functions would be the same)
• output (and support as input) a .tar.gz file with all the original downloaded file from the rM. the idea is that you might want to process them differently at a later time, while meanwhile you might have deleted the files on the device itself. if the .tar.gz file is used as input, no ssh connection to the rM is needed
• in case of multiple matches, show also the visibleName and not only the uuid and lastModDate to help with the selection
• add svg optimization via svgo if present
• add pdf conversion via alternative methods (e.g. I use inkscape as default, as I thought it gave me the best results)
• add some arguments options, hopefully self-explanatory. I confess one might be related to my workflow alone, which is the askrename. In fact, I tend to leave a default name for my notes (e.g. Notebook32), so that looking at the created pdf and being offered a chance of renaming I can replace that without a second cmd.
• overwrite stroke width and opacity to default values (I was unhappy with the default pdf rendering by rM, which looked nice on the device but uglier in the downloaded pdf)
• increase verbosity (this might be eventually controlled with an arg option

I didn't test all corner cases, plus there is plenty of optimizations possible (e.g. pdf pages w/ no annotations are still converted to svg for the final pdftk combinations) but maybe it's a starting point to keep this useful tool current.

[jackjackk]

@edupont thanks a lot for your review! unfortunately I realized the rm2svg does not support the new .lines format, which is version 5. I was testing it with notebooks created before updating the rM to the latest version, hence with a previous .lines format. Do you know where we can find info to update it? also this c++ code https://github.com/ax3l/lines-are-beautiful/ seemed to not be working after a quick test.

[jackjackk]

Alright, there was an added 4-byte field, not sure what for, but for the moment at least it produces the expected output on a couple of test pages. eventually we will need to figure out what is that.