Improve usability of unit converters

[KiruPoruno]

Currently the unit and currency converters, do their job, somewhat,
however actually invoking them can be annoying and finnicky for various
reasons. So to make a general list of improvements that would
significantly make it more useful and easier to use, this now exists:

• Make scrolling results easier
  • Currently, you've to scroll down and click "Show All" if you want
    any conversions that aren't in the first 5 results, this may
    however lead to accidentally dismissing the search bar all
    together, as you don't have to scroll very far for this to happen,
    this is most notable on devices with smaller screens, or ones with
    a keyboard that takes up a big chunk of the screen
• Allow specifying conversion type
  • Currently you must type the original unit, and then scroll through
    the result to find the exact unit you wanted to convert to, instead
    it should be possible to say, type 1.5 kg to t or 1.5 kg t
• Allow typing full and incomplete unit names
  • Currently typing 10 t works but 10 ton doesn't
  • Currently typing 10 EUR works but 10 EU and 10 EUROS doesn't
• Allow conversions to work with or without spaces
  • Currently typing 1.5 kg works, but 1.5kg does not
  • Currently typing 10 EUR works, but 10EUR does not
• Allow conversions to be case insensitive where it doesn't matter
  • Currently typing 1.5 kg works but 1.5 KG doesn't
  • Currently typing 10 EUR works but 10 eur doesn't
    • [Feature Request] Allow lowercase currency names #135

These are just some of the improvements that would make me actually want
to use it, instead of a unit conversion app, and or a search engine,
right now it's too clunky and finnicky to actually be useful.

[Dunexus]

* [ ]  Allow specifying conversion type
  
  * Currently you must type the original unit, and then scroll through
    the result to find the exact unit you wanted to convert to, instead
    it should be possible to say, type `1.5 kg to t` or `1.5 kg t`

This one is already implemented but through a different syntax. Try 1.5kg >> t.
Maybe it could support other keyword than >> tho.

* [ ]  Allow conversions to work with or without spaces
  
  * Currently typing `1.5 kg` works, but `1.5kg` does not
  * Currently typing `10 EUR` works, but `10EUR` does not

This also affects starting a timer. Typing 1 min displays the "Start timer" button but 1min doesn't.

[MM2-0]

Maybe it could support other keyword than >> tho.

- and > works as well.

For currencies, you can also use the currency symbol, £, ¥, €, and so on.

[KiruPoruno]

This one is already implemented but through a different syntax. Try 1.5kg >> t.
Maybe it could support other keyword than >> tho.

Unaware of this one, but it doesn't exactly save time, and is easily forgotten, not to mention not intuitive, I remember first trying to figure out the unit converter and struggling slightly, either due to missing a to or writing the names slightly wrong...

[dotcs]

This also affects starting a timer. Typing 1 min displays the "Start timer" button but 1min doesn't.

I experienced that one also and would love to see that fixed.
Also while "5 min" works, "5 min " (notice space at the end) doesn't. And I never got seconds to work, e.g. "5 min 2 s" does not work.
Additionally "5:02" is only recognized as an alarm but could also be a timer.