Find cmder files when running as Administrator.

When starting a shell as Administrator, the CMDER_ROOT variable is
not propagated from the parent (non-Admin) environment.
Fix this by using paths relative to %ConEmuDir%.

Fixes issue cmderdev#94.

config/ConEmu.xml

@@ -488,7 +488,7 @@
 						<key name="Task1" modified="2013-11-29 16:19:41" build="131107">
 					<value name="Name" type="string" data="{cmd}"/>
 					<value name="GuiArgs" type="string" data=" /icon &quot;%CMDER_ROOT%\cmder.exe&quot;"/>
-					<value name="Cmd1" type="string" data="cmd /k &quot;%CMDER_ROOT%\vendor\init.bat&quot;  -new_console:d:%USERPROFILE%"/>
+					<value name="Cmd1" type="string" data="cmd /k &quot;%ConEmuDir%\..\init.bat&quot;  -new_console:d:%USERPROFILE%"/>
 					<value name="Active" type="dword" data="00000000"/>
 					<value name="Count" type="dword" data="00000001"/>
 					<value name="Hotkey" type="dword" data="00000000"/>

vendor/init.bat

@@ -2,6 +2,11 @@
 :: Sets some nice defaults
 :: Created as part of cmder project
 
+:: Find root dir
+@if not defined CMDER_ROOT (
+    for /f %%i in ("%ConEmuDir%\..\..") do @set CMDER_ROOT="%%~fi"
+)
+
 :: Change the prompt style
 :: Mmm tasty lamb
 @prompt $E[1;32;40m$P$S{git}$S$_$E[1;30;40m{lamb}$S$E[0m