Update lang-pascal.js to include all reserved words and relevant dire…

[JBontes]

…ctives

All reserved words in object-pascal should be included in the pascal keyword list. Also included should be the non-obsolete directives.
Source: http://docwiki.embarcadero.com/RADStudio/Seattle/en/Fundamental_Syntactic_Elements
as well as: http://wiki.freepascal.org/Reserved_words

Finally in addition to {} and (**) comments //... comments are also allowed.

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[JBontes]

I signed it!