Add Noto font and some minor changes

[jdede]

Nice project. Unfortunately, the Liberation Font lacks of some symbols like a telephone. So I switched to Googles Noto font family which aims at supporting the completely support the Unicode standard. Anyway, the Liberation Font is still there and can be used by uncommenting the corresponding definition in the index.php file.

This PR also contains several minor changes as for example:

• Close PHP Tags
• Show available display sizes if not given
• fixed indention / mixing of spaces / tabs
• Add weather symbols to the default font array
• Destroy image objects after usage correctly
• Some minor improvements

It also fixes the problems mentioned in #8

[ghost]

Thx for your work. I'll try to use this font for live weather report...I've tested a METAR decoder so far...maybe then it's not a doorsign anymore but a nice live data example.

[jdede]

@raz0rsdge I also have some nice examples which I would love to merge. But they are all based on this PR. So are there any comments on this particular PR?