Typos in beginners manual

Please add all the errors you find from the beginners manual ([mp-cb-en.pdf ] and [ms-cb-en.pdf ])

Page numbers refer to the version for printing, version of 1999-05-27.

A revised version and versions in new languages are planned: see Revision and translations of “ConTeXt, an excursion”.

where	description
0	the correct e-mail address for pragma is [[1]].
7	run `texexec`, not `context`. (Syntax is the same)
8	`\type{\}` or `\textbackslash` is missing from the tables 3.1/3.2
24	`\placefigure` is missing { } around `\startcombination` ... `\stopcombination`
24	`\stopcombinatie` → `\stopcombination`
56-58	The second, braced argument for `\in` and `\at` can be used to create constructions like `\in{figure}{a}[fig:boats]` which would give you "In figure 25.1a"