Nicer-looking disambiguation in :printdef

Now, it only shows full names in cases of ambiguity.
Merge pull request #1544 from david-christiansen/pprint-printdef

Nicer-looking disambiguation in :printdef
New command :pprint for outputting paper/slide bits

The command:

:pprint fmt width n

outputs the definition of name n for format FMT, with a screen width of
WIDTH columns.

:pprint fmt width tm

outputs the term TM.

The allowed formats are "html" and "latex".
Merge pull request #1547 from david-christiansen/pprint-command

New command :pprint for outputting paper/slide bits
Add benchmark pidigits

Memory usage is quite high
Properly highlight constants in :pprint
Let IDESlave run :pprint
Some comments for pidigits
First renaming attempt
Renaming of built-in datatypes works finally
Finished making standard library naming consistent
Fixed some tests broken under renaming
Added update about renaming to CHANGELOG
Merge pull request #1550 from david-christiansen/pprint-command

Improvements to :pprint - constant highlighting and IDE support
Merge pull request #1552 from Helkafen/benchmarks

Benchmarks
Fixed some accidentally wrong renamings.
Also, adapted some tests to the new names
Fixed broken provider test after providing `()` as `Unit` too
javascript: added LFNegate primitive
Fixed lack of renaming of `lift` to `Lift` in test
Merge pull request #1555 from raichoo/master

javascript: added LFNegate primitive