Add MC sequence

This sequence control when the printer is enabled or disabled. This
sequence control the behaviour of the -o option.
Style matters.
Style cleanup.

Add some note about the main reason why st is still that big.
Add MC for a single line

This sequence print the current line. It is different to the
'printer on' sequence, where all the characters that arrive to the
terminal are printer. Here only the ascii characters are printed.
Add MC for the full screen

This sequence is very useful because allows comunicate the content
of the terminal to another program.
Add key definition for printer sequences

These new combinations generate the same behaviour (basically) of
vt102. It is a good way of communicating st with other programs.

[0] http://www.vt100.net/docs/vt102-ug/chapter2.html
Add sequence for printing the current selection

This is very usefull in order to can select what is sent
to the plumber.
Add terminfo entries for printer

These capabilities inform to programs how print in local printer
of the terminal.
Merge branch 'master' of ssh://suckless.org/gitrepos/st
new utf decoder

This patch replaces current utf decoder with a new one, which is ~50
lines shorter and should be easier to understand. Parsing 5 and 6
sequences, if necessary, requires trivial modification of UTF_SIZ
constant and utfbyte, utfmask, utfmin, utfmax arrays.
Fix segfault when pressing PrintScr without a selection
Fixing a compiler warning with the assignment.
There is no need for a full dirt redraw.
Updating the TODO in preparating for 0.5.
0.5 release.