Add Osaka Jade theme to default theme set. (#514)

* Add Osaka Jade Theme

* Use jpg for bg for lower size with no quality difference

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Co-authored-by: Justin Lowry <j.lowry@hey.com>
Co-authored-by: David Heinemeier Hansson <david@hey.com>

themes/osaka-jade/alacritty.toml

@@ -0,0 +1,28 @@
+[colors]
+[colors.primary]
+background = '#111c18'
+foreground = '#C1C497'
+
+[colors.normal]
+black   = "#23372B"
+red     = "#FF5345"
+green   = "#549e6a"
+yellow  = "#459451"
+blue    = "#509475"
+magenta = "#D2689C"
+cyan    = "#2DD5B7"
+white   = "#F6F5DD"
+
+[colors.bright]
+black   = "#53685B"
+red     = "#db9f9c"
+green   = "#143614"
+yellow  = "#E5C736"
+blue    = "#ACD4CF"
+magenta = "#75bbb3"
+cyan    = "#8CD3CB"
+white   = "#9eebb3"
+
+[colors.cursor]
+text   = "#000000"
+cursor = "#D7C995"