Installed Dock Icon Extra gets false case on case-sensitive file system

[Ibn]

Steps to reproduce bug:

1. have OSX on case-sensitive file-system
2. install dock icon Hand-Drawn Dock -  http://www.adiumxtras.com/index.php?a=xtras&xtra_id=3824 (klicked install)
3. selecting dock icon has no effect.

Problem: i did a ktrace on adium and discovered that the dock icon got installed in /Users/ibn/Library/Application Support/Adium 2.0/Dock Icons/HanddrawnFill.Adiumicon but Adium tries to open HanddrawnFill.AdiumIcon with capital "I". got this error with all the dock icons i installed.

ktrace output:

   957 Adium    RET   lstat -1 errno 2 No such file or directory
   957 Adium    CALL  lstat(0xbfffd310,0xbfffd780)
   957 Adium    NAMI  "/Applications/Adium.app/Contents/Resources/Dock Icons"
   957 Adium    RET   lstat 0
   957 Adium    CALL  lstat(0xbfffd390,0xbfffd800)
   957 Adium    NAMI  "/Users/ibn/Library/Application Support/Adium 2.0/Dock Icons/HanddrawnFill.AdiumIcon"
   957 Adium    RET   lstat -1 errno 2 No such file or directory
   957 Adium    CALL  lstat(0xbfffd390,0xbfffd800)
   957 Adium    NAMI  "/Applications/Adium.app/Contents/Resources/Dock Icons/HanddrawnFill.AdiumIcon"
   957 Adium    RET   lstat -1 errno 2 No such file or directory
   957 Adium    CALL  lstat(0xbfffd170,0xbfffd5e0)
   957 Adium    NAMI  "/Applications/Adium.app"
   957 Adium    RET   lstat 0

[evands]

In deference to thorough reporting -- it does win friends and influence people -- I'm reopening #176 and fixing this ancient problem. Duplicate of #176, which is now milestoned 1.1.

[evands]

(In [19250]) Fix the case of the extension when installing AdiumXtras, which makes them work properly on case-sensitive file systems. Fixes #176. Refs #6620.