Rename and consolidate tests in reserved-words directory

test/language/reserved-words/7.6.1-8-4.js

test/language/reserved-words/7.6.1-8-5.js

test/language/reserved-words/7.6.1-8-6.js

test/language/reserved-words/7.6.1-8-7.js

test/language/reserved-words/7.6.1-8-8.js

test/language/reserved-words/7.6.1-8-9.js

test/language/reserved-words/7.6.1.2-1gs.js

test/language/reserved-words/S7.6.1_A1.1.js

test/language/reserved-words/S7.6.1_A1.2.js

test/language/reserved-words/S7.6.1_A1.3.js

...age/reserved-words/ident-name-global-property-accessor.js

...served-words/ident-name-global-property-memberexpr-str.js

...e/reserved-words/ident-name-global-property-memberexpr.js

...ge/reserved-words/ident-name-global-property-prop-name.js

test/language/reserved-words/ident-name-keyword-accessor.js

...guage/reserved-words/ident-name-keyword-memberexpr-str.js

.../language/reserved-words/ident-name-keyword-memberexpr.js

test/language/reserved-words/ident-name-keyword-prop-name.js

...served-words/ident-name-reserved-word-literal-accessor.js

...-words/ident-name-reserved-word-literal-memberexpr-str.js