Fix error message when jumping to pdf from non-.tex-file

[rensbaardman]

There was ST1-syntax being used (the same as in https://github.com/SublimeText/LaTeXTools/issues/51) that caused a Python error. This PR fixes that, so when you are in a non-.tex-file and try to jump to the PDF, it gives the Sublime error "$FILE is not a TeX source file: cannot jump.".

This still leaves another question to me: I encountered this bug when I tried to recompile from a non-.tex-file. In that case, I think there should not be an error message, but instead it should either:

• reload the pdf on the same place if it was already opened
• open the pdf on the first page if it hadn't been open

Should I open an issue for that? I am not familiar enough with the code base to fix it myself.

[r-stein]

Thanks

[rensbaardman]

@r-stein I actually did try to fix the open question I posed: see the new commits.

It solved my problem and I think this should work in all situations, but I'm not familiar enough with the code base to be completely sure. Could you review it?

[ig0774]

@rensbaardman I think I might be willing to merge this, but it's awfully hard to follow what was actually changed in this PR. Could you point out the relevant lines if you remember?

[rensbaardman]

@ig0774 My apologies, looking back this is certainly not a clean PR, and I should have split up the cleaning and the fix. I was trying to do two things:

• the fix for the outdated syntax is in this line
• the fix for jumping from non-.tex files is in these lines.

[ig0774]

@rensbaardman That's fine... that sort of thing happens... made only more difficult by the pending refactors I've just merged in. I think the captures the import part. Thanks!