Revert "themes: make blue more readable"

This reverts commit 5c0167c5e1.

Porkepix on IRC pointed this out and it actually does the reverse of make
blue more readable. compare:

before:
https://framapic.org/EvV0cVyAUKUm/OZIdkLB4pOCn.png

after:
https://framapic.org/hX2gczT1jGMU/jtu3mJ3eQE2E.png

notice the bg of the bar at the bottom now become a lighter blue
making numbers hard to read. the darker blue was chosen because that
is actually the blue color used in xterm and the linux console (or
closer to it with a bit of a muted coloring to it rather than totally
pure). :( so sorry - this IMHO goes backwards and Porkepix did point
it out too.

data/themes/default_colors.in.edc

@@ -5,7 +5,7 @@ color_class { name: "c1";       color:   0   0   0 255; } // COL_BLACK
 color_class { name: "c2";       color: 204  51  51 255; } // COL_RED
 color_class { name: "c3";       color:  51 204  51 255; } // COL_GREEN
 color_class { name: "c4";       color: 204 136  51 255; } // COL_YELLOW
-color_class { name: "c5";       color:  38 139 210 255; } // COL_BLUE
+color_class { name: "c5";       color:  51  51 204 255; } // COL_BLUE
 color_class { name: "c6";       color: 204  51 204 255; } // COL_MAGENTA
 color_class { name: "c7";       color:  51 204 204 255; } // COL_CYAN
 color_class { name: "c8";       color: 204 204 204 255; } // COL_WHITE
@@ -56,7 +56,7 @@ color_class { name: "C0";   color:   0   0   0 255; } // COL_BLACK
 color_class { name: "C1";   color: 204  51  51 255; } // COL_RED
 color_class { name: "C2";   color:  51 204  51 255; } // COL_GREEN
 color_class { name: "C3";   color: 204 136  51 255; } // COL_YELLOW
-color_class { name: "C4";   color:  38 139 210 255; } // COL_BLUE
+color_class { name: "C4";   color:  51  51 204 255; } // COL_BLUE
 color_class { name: "C5";   color: 204  51 204 255; } // COL_MAGENTA
 color_class { name: "C6";   color:  51 204 204 255; } // COL_CYAN
 color_class { name: "C7";   color: 204 204 204 255; } // COL_WHITE