download the build database automatically into the right place

[aaronmcdaid]

It's pretty easy actually, I can do it in a few minutes I think when I put my mind to it!

[aaronmcdaid]

Done, and pushed to your github repo at a new branch called 'downloadBuildDB'. Hopefully, you can just merge with your current 'master'.

A few comments to explain what I did, if you're interested:

• For users who aren't using 1KG, I check if the build db is present and give an error message if not that explains how to download it. (Search for 'Necessary file missing' in ssimp.cc

• If somebody has 1KG downloaded already, but not the build database, then I also give a suitable error message. (Search for 'blddb_file_name' in ssimp.cc)

• for users who are intending to use 1KG, but who haven't already downloaded it, (i.e. the majority of first-time users) I have improved the help message so that it explains how to download the build db. Also, the code that automatically calls 'wget' to download it. So basically, when it downloads 1KG it will also download the build DB. Search for 'drive.switch.ch' in around lines 450-500

[aaronmcdaid]

(You can probably ignore this message. It's only important if you have already pulled from 'downloadBuildDB' in the last two hours. If you did pull already, then you'll need to pull again as I have just pushed another [very unimportant] commit to that branch)

just a minute ago, I made another commit pushed it to 'downloadBuildDB'. One of the error messages was misleading and mixed up the panel file with the build database file