Minor editorial changes to the landing page

[milancurcic]

Mostly punctuation, capitalization, rewording a few things to be more concise, and similar.

[awvwgk]

Just rebuild the locales and it worked like a charm. There is apparently a fuzzy matching against old msgid's which allows to mostly keep the translations correctly in place when updating the po files. All fuzzy matched msgid's will get marked and can be reviewed and updated, all non-matching msgid's are retained and can be reused to by the translator to update the msgtxt entries later. Really like the way gettext works in this.

However, if the po-files are not rebuild the msgid don't match anymore and the translation will be almost completely lost. I wonder whether we can automate this (the po=files have a timestamp, which makes it difficult to discover changes by running the gettext target and just rely on the existence of diffs). Have to think about something better.