emulation: Migrating from terminfo: single-byte control codes

Hardwire the behavior of single-byte control codes (newline, tab etc.) and
closely related ones (e.g. tab stops), rather than relying on terminfo.

Implement CSI n I (n tabs).
emulation: Migrating from terminfo: cursor moving operations

Hardwire the behavior of cursor moving operations, rather than relying on
terminfo.

Remove support for nonstandard "move cursor to lower left corner".
emulation: Migrating from terminfo: insert and erase operations

Hardwire the behavior of insert and erase operations, rather than relying
on terminfo.
emulation: Migrating from terminfo: clear operations

Hardwire the behavior of clear operations, rather than relying on
terminfo.
emulation: Migrating from terminfo: scrolling operations

Hardwire the behavior of scrolling operations, rather than relying on
terminfo.

Make the parameter parsing of scroll regions more compatible with xterm.

Drop support for "cS", there's no corresponding xterm terminfo entry.
emulation: Migrating from terminfo: miscellaneous

Hardwire the behavior of some random operations, rather than relying on
terminfo.

Drop support for "uc", there's no corresponding xterm terminfo entry.
emulation: Remove unused code
widget: Fix disappearing mouse pointer

https://bugzilla.gnome.org/show_bug.cgi?id=725342
iconv: test: Use g_assert_cmpuint
iconv: test: Simplify test setup
iconv: test: Simplify test setup