Using the relative path instead of the absolute path in portable mode for "content"

[enjoying-codes]

It tested & works to change the absolute path of "content" in portable\config file after initial indexing.

For example,

<path recursive="1">D:/GoldenDict-ng/content</path>
<hunspell dictionariesPath="D:/GoldenDict-ng/content/morphology"/>

to

<path recursive="1">./content</path>
<hunspell dictionariesPath="./content/morphology"/>

It's helpful for launching the goldendict.exe in any path in portable mode without additional setting.