Fix uninitialized memory access in switch AST node

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# On branch fix_switch
# Changes to be committed:
#	modified:   src/aparser.c
#	modified:   v7.c
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#	ast.py
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#	ast2
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#	c.js
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#	src/.#main.c
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#	u.js
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Merge pull request #78 from cesanta/fix_switch

Fix uninitialized memory access in switch AST node