Backport and modify canvas v2 from rtorrent-ps

[chros73]

A. Backport canvas v2 from rtorrent-ps:

• replace the previous rtorrent-ps-ch canvas with canvas v2 engine

Take a look at canvas v2 of rTorrent Handbook for more info.

B. Backport patches from rtorrent-ps:

• lt-ps_all_02-better-bencode-errors_all.patch
• ps-dl-ui-find.patch
  • fix ^F binding for 'find' input
• ps-event-view_all.patch
• ps-fix-log-xmlrpc-close_all.patch
• ps-import.return_all.patch
• ps-object_std-map-serialization_all.patch
• ps-silent-catch_all.patch

C. Also backport new commands from rtorrent-ps:

• string.len, string.join, string.split, string.substr, string.shorten, string.equals, string.stratswith, string.endswith, string.strip, string.lstrip, string.rstrip, string.lpad, string.rpad
• array.at
• system.has, system.has.list, system.has.private_methods, system.has.public_methods, system.client_version.as_value
• d.custom.if_z, d.custom.set_if_z, d.custom.erase, d.custom.keys, d.custom.items, d.custom.toggle, d.custom.as_value
• import.return, do
• d.tracker_alias, d.message.alert
• ui.canvas_color[.set]
• ui.column.spec, ui.column.hide, ui.column.show, ui.column.is_hidden, ui.column.hidden.list, ui.column.sacrificial.list, ui.column.sacrificed
• ui.find.next, ui.find.term
• ui.color.custom[x]
• convert.time_delta

Take a look at command reference of rTorrent Handbook for more info.

D. Remove old commands from rtorrent-ps-ch:

• d.ui.* commands
• chars.* command group: chars.chop, chars.pad
  • use string.substr/string.shorten, string.lpad/string.rpad instead

E. Modify canvas v2 a bit:

• move column titles with couple of characters
• in render_columns method:
  • chop column title as well (not just column content)
  • auto-add +1 character at "Advance position"
    • shorten column/color lengths by 1
    • remove the unnecessary extra character from column definitions
  • define extra colorization:
    • COL_ACTIVE_TIME (C70) for "Uprate or approximate time since last active state" column
    • COL_UNSAFE_DATA (C71) for "Unsafe data" column
    • COL_THROTTLE_CH (C72) for "Throttle" column
    • COL_ETA_TIME (C73) for "ETA/last_xfer" column
• remove F bindings from ui.find.term, F3 still works
  • F binding is for tempfilter
• make ☢ and ℞ (connected peers) built in columns sacrificiable
• make ❢ (message or alert) and ☯ (ratio) built-in columns 1 character width (instead of 2)
• modify ⣿ (progress) built-in column to take into account partially done downloads
  • don't modify corresponding colorizing, so it can be clear which downloads are only partially done
• remove spacer between Name and Flagged columns
• remove deprecated ui.style.progress and ui.style.ratio commands
• remove (again) the seemingly unnecessary/buggy Canvas::cleanup() call

F. Fixes:

• fix endless loop in ui_find_next() when no download is selected and term couldn't be find

G. Others:

• update color schemes in contrib directory

Big thanks to @pyroscope for his work!

[chros73]

@pyroscope: your changes are freeking awesome! Thanks! I like the auto sacrifitial columns, the extra color defs, the find feature is just amazing :)

I modified a bit, the changes are small (there're couple of revert commits as well :) ), please go through it (apart from the first big commit). These are the important ones:

• chop column title as well (not just column content)
• auto-add +1 character at "Advance position" (shorten column/color lengths by 1, remove the unnecessary extra character from column definitions)
  • it's not just a cosmetic change: e.g. we can get rid of 1 math command from progress and ratio columns, and we don't have to use extra commands (e.g. string.substr) for columns that contain variable lenght text (e.g. data dir)
• fix ^F binding for 'find' input (the override didn't work in 0.9.7 for whatever reason)
• I added 2 new commands as well :)

Maybe I'll change the column order and/or color definitions (I'm not sure yet), but I won't change anything else logic wise.