Update changelog for versions 0.0.5.6 and 0.0.5.7

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branch : custombuttons-0-0-5-8
Update changelog

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branch : custombuttons-0-0-5-8
Change version number

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branch : custombuttons-0-0-5-8
Tabify overlay.js

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branch : tabify-source
Tabify cbbutton.js

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branch : tabify-source
Merge with "tabify-source" branch
Merge pull request from git repository (Add "Move to ..." and "Remove from ..." items (Firefox 29+)
Marked compatible with Firefox 32.0a1

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branch : custombuttons-0-0-5-8
Merge with branch 'custombuttons-0-0-5-8'
Merge with 'default' branch

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branch : tabify-source
Tabify after merge with 'default' branch

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branch : tabify-source
Merge with 'tabify-source' branch
Tabify *.js sources

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branch : tabify-source
Merge with 'tabify-source' branch
# Fixed: "Customize…" context menu item doesn't work in SeaMonkey 2.12 and higher

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rename : chrome/custombuttons/content/custombuttons/Seamonkey21Overlay.xul => chrome/custombuttons/content/custombuttons/seamonkey/below_2.12b1/SeamonkeyOverlay.xul
rename : chrome/custombuttons/content/custombuttons/SeamonkeyOverlay.xul => chrome/custombuttons/content/custombuttons/seamonkey/below_2.1a1pre/SeamonkeyOverlay.xul