JS parser: removed magic string
JS parser: added NUMBER literal types

Splitted NUMBER literal type into NUMBER_INT and NUMBER_DOUBLE
JS parser: added insideFunction flag
JS parser: literals creation
~~ auto reformat
JS parser: made methods static where possible
JS parser: renamed sourceNameStub to comply with a codestyle (UPPERCASE)
JS parser: added description string to constructor arguments
JS backend: added jsCode test cases
JS backend: added jsCode definition
JS backend: expand jsCode at translator
JS backend minor: formatting
JS parser: removed @ from @author tag because of JetCodeConformanceTest
JS parser: removed unused class
JS parser: pass Parser additional parameters using ParsingConfig
JS parser: fixed labelled break/continue
~~JS parser: added jsExpression intrinsic
~~ prohibit using jsCode as expression, use jsExpression instead