Customizing icons for "process" component (also applies mostly to "battery" and "datetime")

[michaelbrusegard]

• As a user I only want to show the icon:

tab_active = {
  { "process", icons_only = true }
}

• As a user I want my own custom icon for every process:

tab_active = {
  { "process", icon = wezterm.nerdfonts.my_cool_icon, process_to_icon = nil }
}

• As a user I want the default color for all icons:

tab_active = {
  { "process", icon = { color = false }
}

• As a user I want to customize the icon color for every process:

tab_active = {
  { "process", icon = { color = { fg = "#ff0000" } } }
}

• As a user I want my own custom icon with custom color and alignment:

tab_active = {
  { "process", icon = { wezterm.nerdfonts.my_cool_icon, color = { fg = "#ff0000", bg = "#00ff00" }, align = "right" }, process_to_icon = nil }
}

• As a user I don't want to show the icon:

tab_active = {
  { "process", icons_enabled = false }
}